Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2016	Nov. 07, 2016
Document and Entity Information
Entity Registrant Name	Bellerophon Therapeutics, Inc.
Entity Central Index Key	0001600132
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		14,506,997
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 3,930	$ 6,260
Marketable securities	7,230	17,807
Prepaid expenses and other current assets	6,365	5,385
Total current assets	17,525	29,452
Restricted cash, non-current	457	457
Other non-current assets	3,304	6,701
Property and equipment, net	1,498	1,799
Total assets	22,784	38,409
Current liabilities:
Accounts payable	2,235	1,613
Accrued research and development	1,085	2,825
Accrued expenses	1,302	3,487
Due to Ikaria, Inc.	166	148
Total current liabilities	4,788	8,073
Total liabilities	4,788	8,073
Commitments and contingencies
Stockholders’ equity:
Common stock, $0.01 par value per share; 125,000,000 shares authorized, 14,506,997 and 13,130,800 shares issued and outstanding at September 30, 2016 and December 31, 2015, respectively	145	131
Preferred stock, $0.01 par value per share; 5,000,000 shares authorized, zero shares issued and outstanding at September 30, 2016 and December 31, 2015, respectively	0	0
Additional paid-in capital	134,921	130,902
Accumulated other comprehensive loss	(1)	(19)
Accumulated deficit	(117,069)	(100,678)
Total stockholders’ equity	17,996	30,336
Total liabilities and stockholders’ equity	$ 22,784	$ 38,409

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	125,000,000	125,000,000
Common stock, shares issued (in shares)	14,506,997	13,130,800
Common stock, shares outstanding (in shares)	14,506,997	13,130,800
Preferred tock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Operating expenses:
Research and development	$ 2,472	$ 7,090	$ 11,539	$ 25,036
General and administrative	1,745	4,329	4,926	12,337
Total operating expenses	4,217	11,419	16,465	37,373
Other operating income	0	250	0	1,667
Loss from operations	(4,217)	(11,169)	(16,465)	(35,706)
Interest income	22	27	74	73
Loss before taxes	(4,195)	(11,142)	(16,391)	(35,633)
Income tax benefit	0	0	0	0
Net loss	$ (4,195)	$ (11,142)	$ (16,391)	$ (35,633)
Weighted average shares outstanding:
Basic and diluted (in shares)	13,854,188	12,911,905	13,335,358	12,012,002
Net loss per share:
Basic and diluted (in dollars per share)	$ (0.30)	$ (0.86)	$ (1.23)	$ (2.97)

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (4,195)	$ (11,142)	$ (16,391)	$ (35,633)
Other comprehensive (loss) income
Unrealized gain (loss) on available-for-sale marketable securities	(3)	1	18	1
Total other comprehensive (loss) income	(3)	1	18	1
Comprehensive loss	$ (4,198)	$ (11,141)	$ (16,373)	$ (35,632)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Condensed Consolidated Statements of Changes in Stockholders'/Members Equity (Unaudited) - 9 months ended Sep. 30, 2016 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at beginning of period (in shares) at Dec. 31, 2015	13,130,800	13,130,800
Balance at beginning of period at Dec. 31, 2015	$ 30,336	$ 131	$ 130,902	$ (19)	$ (100,678)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(16,391)				(16,391)
Other comprehensive income	$ 18			18
Sale of common stock in shelf offering, shares	973,024	973,024
Sale of common stock in shelf offering, value	$ 2,013	$ 10	2,003
Stock-based compensation, net (in shares)		403,173
Stock-based compensation, net	$ 2,020	$ 4	2,016
Balance at end of period (in shares) at Sep. 30, 2016	14,506,997	14,506,997
Balance at end of period at Sep. 30, 2016	$ 17,996	$ 145	$ 134,921	$ (1)	$ (117,069)

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net loss	$ (16,391)	$ (35,633)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	301	273
Stock-based compensation	2,148	1,244
Accretion and amortization of discounts and premiums on marketable securities, net	29	5
Changes in operating assets and liabilities:
Receivables due from Ikaria, Inc.	0	(250)
Prepaid expenses and other current assets	(980)	158
Restricted cash held for Ikaria, Inc.	0	(6,949)
Restricted cash held as security deposit	0	(457)
Other non-current assets	3,397	0
Accounts payable, accrued research and development, and accrued expenses	(3,316)	(1,826)
Amounts due to Ikaria, Inc.	18	570
Net cash used in operating activities	(14,794)	(28,967)
Cash flows from investing activities:
Capital expenditures	(22)	(424)
Purchase of marketable securities	0	(18,865)
Proceeds from sale of marketable securities	10,566	1,470
Net cash provided by (used in) investing activities	10,544	(17,819)
Cash flows from financing activities:
Proceeds from sale of membership units	0	1
Proceeds received from exercise of stock options	0	51
Proceeds from sale of common stock in ATM Offering, net of commissions and offering expenses	2,048	0
Tax withholding payments for stock compensation	(128)
Proceeds from issuance of common stock from initial public offering, net of issuance costs	0	53,827
Net cash provided by financing activities	1,920	53,879
Net change in cash and cash equivalents	(2,330)	7,093
Cash and cash equivalents at beginning of period	6,260	16,815
Cash and cash equivalents at end of period	3,930	23,908
Non-cash financing activities:
Unpaid expenses related to ATM Offering	35	0
Non-cash investing activities:
Change in unrealized holding losses on marketable securities, net	$ 18	$ 1

Organization and Nature of the Business

9 Months Ended

Sep. 30, 2016

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Nature of the Business

Bellerophon Therapeutics, Inc., or the Company, is a clinical-stage therapeutics company focused on developing innovative products at the intersection of drugs and devices that address significant unmet medical needs in the treatment of cardiopulmonary diseases. The focus of the Company is the continued development of its nitric oxide therapy for patients with pulmonary hypertension, or PH, using its proprietary delivery system, INOpulse, with pulmonary arterial hypertension, or PAH, representing the lead indication.

The Company was formerly the research and development operating segment of Ikaria, Inc. (a subsidiary of Mallinckrodt plc), or Ikaria. In 2013, Ikaria completed an internal reorganization of the assets and subsidiaries of its two operating segments. In connection with the internal reorganization, Ikaria formed Bellerophon Therapeutics LLC as a new wholly-owned subsidiary and transferred the research and development-related assets related to INOpulse for PAH and INOpulse for PH-COPD to the Company and/or its subsidiaries. In February 2015, the Company converted from a limited liability company to a C-corporation. For periods prior to February 2015, references to the Company refer to Bellerophon Therapeutics LLC.

The Company’s business is subject to significant risks and uncertainties, including but not limited to:


•	The risk that the Company will not achieve success in its research and development efforts, including clinical trials conducted by it or its potential collaborative partners.


•	The expectation that the Company will experience operating losses for the next several years.


•	Decisions by regulatory authorities regarding whether and when to approve the Company’s regulatory applications as well as their decisions regarding labeling and other matters which could affect the commercial potential of the Company’s products or product candidates.


•	The risk that the Company will fail to obtain adequate financing to meet its future operational and capital needs.


•	The risk that key personnel will leave the Company and/or that the Company will be unable to recruit and retain senior level officers to manage its business.

On February 2, 2015, the Company effected a reverse unit split of its outstanding units at a ratio of one unit for every 12.5257 units previously held.

On February 19, 2015, the Company completed the sale of 5,000,000 shares of common stock, or the IPO, at a price to the public of $12.00 per share, resulting in net proceeds to the Company of $51.9 million after deducting underwriting discounts and commissions of $4.2 million and offering costs of $3.9 million. The Company’s common stock began trading on the NASDAQ Global Market under the symbol “BLPH” on February 13, 2015.

On May 5, 2016, the Company filed a shelf registration statement with the Securities and Exchange Commission, or the SEC, on Form S-3, which as amended became effective on May 23, 2016. The shelf registration will allow the Company to issue, from time to time at prices and on terms to be determined prior to the time of any such offering, up to $30.0 million of any combination of the Company’s common stock, preferred stock, debt securities, warrants, rights, purchase contracts or units, either individually or in units.

On May 27, 2016, the Company entered into an At Market Issuance Sales Agreement, or Sales Agreement, with FBR Capital Markets & Co. and MLV & Co. LLC, or the Distribution Agents, pursuant to which the Company may issue and sell shares of the Company's common stock having an aggregate offering price of up to $5.7 million through the Distribution Agents. Any sales of shares of the Company's common stock pursuant to the Sales Agreement, or ATM Offering, will be made under the Company’s effective shelf registration statement on Form S-3 and the related prospectus supplement. As of September 30, 2016, the Company has sold 973,024 shares for gross and net proceeds of $2.2 million and $2.0 million, respectively.

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies (a) Basis of Presentation The accompanying unaudited condensed consolidated financial statements were prepared following the requirements of the Securities and Exchange Commission for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by accounting principles generally accepted in the United States of America, or U.S. GAAP, can be condensed or omitted. The Company operates in one reportable segment and solely within the United States. Accordingly, no segment or geographic information has been presented. The Company is responsible for the unaudited condensed consolidated financial statements. The condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair presentation of the Company’s financial position, results of operations, comprehensive loss and its cash flows for the periods presented. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2015, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015. The results of operations for the three and nine months ended September 30, 2016 for the Company are not necessarily indicative of the results expected for the full year. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of costs and expenses during the reporting period, including accrued expenses, accrued research and development expenses, stock-based compensation, and income taxes. Actual results could differ from those estimates. (b) Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity date of three months or less to be cash equivalents. All investments with maturities of greater than three months from date of purchase are classified as available-for-sale marketable securities. (c) Stock-Based Compensation The Company accounts for its stock-based compensation in accordance with Accounting Standards Codification, or ASC, 718 Compensation- Stock Compensation, which establishes accounting for share-based awards, including stock options and restricted stock, exchanged for services and requires companies to expense the estimated fair value of these awards over the requisite service period. The Company recognizes stock-based compensation expense in operations based on the fair value of the award on the date of the grant. The resulting compensation expense is recognized on a straight-line basis over the requisite service period or sooner if the awards immediately vest. The Company determines the fair value of stock options issued using a Black-Scholes-Merton option pricing model. Certain assumptions used in the model include expected volatility, dividend yield, risk-free interest rate, and expected term. For restricted stock, the fair value is the closing market price per share on the grant date. See Note 6 - Stock-Based Compensation for a description of these assumptions. (d) Income Taxes Prior to its conversion to a Delaware corporation in February 2015, the Company was a Delaware limited liability company, or LLC, that passed through income and losses to its members for U.S. federal and state income tax purposes. As a result of its conversion to a Delaware corporation, the Company recognized deferred income taxes through income tax expense related to temporary differences that existed as of the date of its tax status change. The Company uses the asset and liability approach to account for income taxes as required by ASC 740, Income Taxes, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Valuation allowances are provided when necessary to reduce deferred tax assets to the amount expected to be realized, on a more likely than not basis. The Company recognizes the benefit of an uncertain tax position that it has taken or expects to take on income tax returns it files if such tax position is more likely than not to be sustained on examination by the taxing authorities, based on the technical merits of the position. These tax benefits are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate resolution. The Company’s estimated tax rate for 2016 is expected to be zero because the Company expects to generate additional losses and currently has a full valuation allowance. The deferred tax assets balance before valuation allowance as of September 30, 2016 was approximately $47.7 million. The increase in deferred tax assets in the three and nine months ended September 30, 2016 is principally due to the year-to-date loss, adjusted for nondeductible items including stock compensation expense related to the Company’s equity incentive plan, the nondeductible portion of orphan drug costs, and orphan drug federal income tax credits. The valuation allowance is required until the Company has sufficient positive evidence of taxable income necessary to support realization of its deferred tax assets. The Company did not have material uncertain tax positions as of September 30, 2016. (e) Marketable Securities The Company’s marketable securities consist of federally insured certificates of deposit classified as available-for-sale that are recorded at amortized cost, which approximates fair value, and corporate or agency bonds classified as available-for-sale that are recorded at fair value. Unrealized gains and losses are reported as accumulated other comprehensive (loss) income, except for losses from impairments which are determined to be other-than-temporary. Realized gains and losses, and declines in value judged to be other-than-temporary on available-for-sale securities are included in the determination of net loss and are included in interest income, at which time the average cost basis of these securities are adjusted to fair value. Fair values are based on quoted market prices at the reporting date. Interest on available-for-sale securities are included in interest income. (f) Research and Development Expense Research and development costs are expensed as incurred. These expenses include the costs of the Company’s proprietary research and development efforts, as well as costs incurred in connection with certain licensing arrangements. Upfront and milestone payments made to third parties in connection with research and development collaborations are expensed as incurred up to the point of regulatory approval. Payments made to third parties upon or subsequent to regulatory approval are capitalized and amortized over the remaining useful life of the related product. The Company also expenses the cost of purchased technology and equipment in the period of purchase if it believes that the technology or equipment has not demonstrated technological feasibility and it does not have an alternative future use. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and are recognized as research and development expense as the related goods are delivered or the related services are performed. (g) New Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2018. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is assessing ASU 2014-09’s impact and will adopt it when effective. In August 2014, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, 2014-15, “Presentation of Financial Statements - Going Concern: Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” This guidance clarifies that an entity’s management should evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued. The amendments in this update are effective for annual reporting periods ending after December 15, 2016, and annual and interim periods thereafter, and early application is permitted. The Company is assessing ASU 2014-15’s impact and will adopt it when effective. In January 2016, the FASB issued ASU 2016-01, "Financial Instruments - Overall - Recognition and Measurement of Financial Assets and Financial Liabilities," which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. This standard will be effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company is assessing ASU 2016-01’s impact and will adopt it when effective. In February 2016, the FASB issued ASU 2016-02, "Leases," which is intended to improve financial reporting about leasing transactions. This standard requires a lessee to record on the balance sheet the assets and liabilities for the rights and obligations created by lease terms of more than 12 months. This standard will be effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is assessing ASU 2016-02’s impact and will adopt it when effective. In March 2016, the FASB issued ASU 2016-09, "Compensation - Stock Compensation - Improvements to Employee Share-Based Payment Accounting" which provides for simplification of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. This standard will be effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The Company is assessing ASU 2016-09’s impact and will adopt it when effective. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows: Clarification of Certain Cash Receipts and Cash Payments”, which eliminates the diversity in practice related to the classification of certain cash receipts and payments in the statement of cash flows, by adding or clarifying guidance on eight specific cash flow issues. ASU 2016-15 is effective for annual and interim reporting periods beginning after December 15, 2017 and early adoption is permitted. ASU 2016-15 provides for retrospective application for all periods presented. The Company is assessing ASU 2016-15’s impact and will adopt it when effective.

Liquidity	9 Months Ended
Liquidity	Sep. 30, 2016
Liquidity
Liquidity	Liquidity In the course of its development activities, the Company has sustained operating losses and expects such losses to continue over the next several years. The Company had cash and cash equivalents of $3.9 million and marketable securities of $7.2 million as of September 30, 2016. The Company received net proceeds of $51.9 million in February 2015 as a result of the IPO, after deducting underwriting discounts and commissions of $4.2 million and offering costs of $3.9 million. The Company expects to continue to incur significant expenses and operating losses for the foreseeable future as it continues the development and clinical trials of, and seek regulatory approval for, its product candidates. The Company's primary uses of capital are, and it expects will continue to be, compensation and related expenses, third-party clinical research and development services, contract manufacturing services, laboratory and related supplies, clinical costs, legal and other regulatory expenses and general overhead costs. The Company's existing cash and cash equivalents and marketable securities as of September 30, 2016 will be used primarily to fund the first of two INOpulse for PAH Phase 3 trials, in which the Company enrolled the first patient in June 2016. As of September 30, 2016, the Company had $8.6 million prepayments of research and development expenses related to its amended drug supply agreement with Ikaria and the clinical research organization it has partnered with for the first of the two Phase 3 clinical trials for INOpulse for PAH The corresponding prepayments balance as of December 31, 2015 was $11.3 million. On May 27, 2016, the Company entered into a Sales Agreement, with Distribution Agents, pursuant to which the Company may issue and sell shares of the Company's common stock having an aggregate offering price of up to $5.7 million through the Distribution Agents. Any sales of shares of the Company's common stock pursuant to the Sales Agreement, or the ATM Offering, will be made under the Company’s effective shelf registration statement on Form S-3 and the related prospectus supplement dated May 27, 2016 and filed with the SEC on May 27, 2016. As of September 30, 2016, the Company had sold 973,024 shares for gross and net proceeds of $2.2 million and $2.0 million, respectively. During December 2015, the Company entered into a letter agreement with Global Corporate Finance, or GCF. In accordance with the terms of the letter agreement, the Company has agreed to place with GCF up to $20.0 million of its common stock subject to the execution of a definitive share purchase agreement and registration rights agreement. The Company may not draw down amounts that would result in GCF owning more than 19.9% of the Company's outstanding shares. The first two drawdowns under this letter agreement may not exceed $2.0 million. Thereafter, the drawdown amounts will depend on the average daily trading volume of the Company's shares. At September 30, 2016, the amount that could be drawn down under this agreement was approximately $4.0 million. The Company continues to pursue potential sources of funding, including equity financing. The Company believes, as of September 30, 2016, its existing funds, combined with the additional funding available under the ATM Offering, along with alternatives available to the Company, as discussed above, will be sufficient to satisfy its operating cash needs for at least the next 12 months. However, if the Company is unable to raise capital on acceptable terms, it plans to reduce research and development expenses until additional funding becomes available by postponing certain programs and to reduce certain general and administrative expenses, as well as move certain external costs in house. The Company’s estimates and assumptions may prove to be wrong, and the Company may exhaust its capital resources sooner than expected. The process of testing product candidates in clinical trials is costly, and the timing of progress in clinical trials is uncertain. Because the Company’s product candidates are in clinical development and the outcome of these efforts is uncertain, the Company cannot estimate the actual amounts that will be necessary to successfully complete the development and commercialization, if approved, of its product candidates or whether, or when, the Company may achieve profitability. Until such time, if ever, as the Company can generate substantial product revenues, it expects to finance its cash needs through a combination of equity and debt offerings, existing working capital and funding from potential future collaboration arrangements. To the extent that the Company raises additional capital through the future sale of equity or debt, the ownership interest of its existing stockholders will be diluted, and the terms of such securities may include liquidation or other preferences or rights such as anti-dilution rights that adversely affect the rights of the Company's existing stockholders. If the Company raises additional funds through strategic partnerships in the future, it may have to relinquish valuable rights to its technologies, future revenue streams or product candidates or grant licenses on terms that may not be favorable to it. If the Company is unable to raise additional funds through equity or debt financings when needed, it may be required to delay, limit, reduce or terminate its product development or future commercialization efforts or grant rights to develop and market product candidates that it would otherwise prefer to develop and market itself. If the Company is unable to raise capital when needed, it could be forced to delay, reduce or eliminate its product development programs or commercialization efforts. Moreover, if the Company is unable to obtain additional funds on a timely basis, there will be substantial doubt about its ability to continue as a going concern.

Marketable Securities

9 Months Ended

Sep. 30, 2016

Marketable Securities [Abstract]

Marketable Securities

The Company considers all of its investments to be available-for-sale. Marketable securities as of September 30, 2016 consist of the following (in thousands):



	Amortized Cost	Gross Unrealized Gains	Gross Unrealized Losses		Fair Value
Certificates of deposit	5,274	—	—		5,274
Corporate bonds	1,957	—	(1	)	1,956
Total	7,231	—	(1	)	7,230

Marketable securities as of December 31, 2015, consist of the following (in thousands):



	Amortized Cost	Gross Unrealized Gains	Gross Unrealized Losses		Fair Value
Certificates of deposit	10,140	—	—		10,140
Corporate bonds	4,938	—	(11	)	4,927
Agency bonds	2,748	—	(8	)	2,740
Total	17,826	—	(19	)	17,807

Maturities of marketable securities classified as available-for-sale were as follows at September 30, 2016 and December 31, 2015 (in thousands):



	September 30, 2016	December 31, 2015
Due within one year	6,533	10,230
Due after one year through two years	697	7,577
	7,230	17,807

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective tax rate for each of the three and nine month periods ended September 30, 2016 and 2015, respectively was 0.0%. For the three and nine months ended September 30, 2016 and 2015, the effective rate was lower than the federal statutory rates primarily due to losses incurred and a full valuation allowance on deferred tax assets. As of September 30, 2016, there were no material uncertain tax positions. There are no tax positions for which a material change in any unrecognized tax benefit liability is reasonably possible in the next 12 months.

Stock-Based Compensation

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

Determining the appropriate fair value of stock-based awards requires the input of subjective assumptions, including the fair value of the Company’s units (prior to the IPO date) and for options, the expected term of the option and expected volatility. The Company uses the Black-Scholes-Merton option pricing model to value its stock option awards. The assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, stock-based compensation expense could be materially different for future awards. The expected term of stock options is estimated using the “simplified method,” as the Company has no historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock options grants. The simplified method is based on the average of the vesting tranches and the contractual life of each grant. For volatility, the Company uses comparable public companies as a basis for its expected volatility to calculate the fair value of option grants due to its limited history as a public company. The risk-free interest rate is based on U.S. Treasury notes with a term approximating the expected term of the option. The estimation of the number of stock awards that will ultimately vest requires judgment, and to the extent actual results or updated estimates differ from the Company’s current estimates, such amounts will be recorded as an adjustment in the period in which estimates are revised.

Bellerophon 2015 and 2014 Equity Incentive Plans

During 2015, the Company adopted the 2015 Equity Incentive Plan, or the 2015 Plan, which provides for the grant of options, restricted stock and other forms of equity compensation.

As of September 30, 2016, there was approximately $2.7 million of total unrecognized compensation expense related to unvested stock awards. This expense is expected to be recognized over a weighted-average period of 1.9 years.

No tax benefit was recognized during the nine months ended September 30, 2016 and 2015 related to stock-based compensation expense since the Company incurred operating losses and has established a full valuation allowance to offset all the potential tax benefits associated with its deferred tax assets.

Stock Options

Compensation expense is measured based on the fair value of the stock option on the grant date and is recognized on a straight-line basis over the requisite service period, or sooner if vesting occurs sooner than on a straight-line basis. Stock options are forfeited if the employee ceases to be employed by the Company prior to vesting.

During 2014, the Company adopted the 2014 Equity Incentive Plan, or the 2014 Plan, which provided for the grant of stock options. Following the effectiveness of the Company’s registration statement filed in connection with its IPO, no stock options may be granted under the 2014 Plan. The awards granted under the 2014 Plan generally have a vesting period of four years, of which 25% of the awards vest on the second anniversary of grant date, 25% vest on the third anniversary and the remaining 50% vest on the fourth anniversary of the grant date. The awards granted under the 2015 Plan have a vesting period of either three or four years, of which equal annual installments vest over the vesting period, either beginning on the date of grant or on the one-year anniversary of the date of grant.

The weighted average grant-date fair value of stock options issued during the nine months ended September 30, 2016 and 2015 was $1.52 and $6.55, respectively. The following are the weighted average assumptions used in estimating the fair value of stock options issued during the nine months ended September 30, 2016 and 2015:



	Nine Months Ended September 30, 2016		Nine Months Ended September 30, 2015
Valuation assumptions:
Risk-free rate	1.34	%	1.60	%
Expected volatility	81.8	%	79.2	%
Expected term (years)	6.1		6.1
Dividend yield	—		—

A summary of stock option activity under the 2015 Plan and 2014 Plan for the nine months ended September 30, 2016 is presented below:



	Options		Range of Exercise Price				Weighted Average Price		Weighted Average Remaining Contractual Life (in years)
Options outstanding as of December 31, 2015	705,180		$	4.12	-	13.28	$	12.08	8.7
Granted	230,000		1.40		-	2.30	2.17
Exercised	—
Forfeited	(45,072	)	10.22		-	13.28	11.68
Options outstanding as of September 30, 2016	890,108		$	1.40	-	13.28	$	9.54	8.3
Options vested and exercisable as of September 30, 2016	334,025		$	4.12	-	13.28	$	12.58	7.8

Restricted Stock

A summary of restricted stock activity under the 2015 Plan for the nine months ended September 30, 2016 is presented below:



	Shares		Weighted Average Fair Value		Aggregate Grant Date Fair Value (in millions)			Weighted Average Remaining Contractual Life (in years)
Restricted stock outstanding as of December 31, 2015	77,793		$	3.99	$	0.3		0.7
Granted	519,871		2.40		1.2
Released	(251,842	)	2.86		(0.7		)
Forfeited	(24,001	)	3.69		(0.1		)
Restricted stock outstanding as of September 30, 2016	321,821		$	2.33	$	0.7		0.3

Ikaria Equity Incentive Plans prior to February 12, 2014

Stock Options

Following the internal reorganization of Ikaria, in February 2014, Ikaria distributed all of the Company's then outstanding units to its stockholders through the payment of a special dividend on a pro rata basis based on each stockholder’s ownership of Ikaria capital stock. The Company refers to Ikaria’s distribution of the Company's then outstanding units to its stockholders as the Spin-Out. In February 2014, prior to the Spin-Out, each Ikaria stock option, other than stock options held by non-accredited investors who were also not employees of Ikaria, was adjusted such that it became an option to acquire the same number of shares of Ikaria non-voting common stock as were subject to the Ikaria stock option, or an Adjusted Ikaria Option, and an option to acquire the same number of non-voting limited liability company units of the Company as the number of shares of Ikaria non-voting common stock that were subject to the Ikaria stock option, or a Bellerophon Option. There were 618,212 Bellerophon Options issued as a result of the adjustment of Ikaria stock options. The vesting of each Adjusted Ikaria Option and Bellerophon Option was fully accelerated on the date of the Spin-Out and all related compensation expense was recognized as an expense by Ikaria.

Prior to and in connection with the Spin-Out, the exercise price of each Adjusted Ikaria Option and Bellerophon Option was adjusted by allocating the relative post Spin-Out estimated fair values of Ikaria and the Company in a ratio of 85% and 15%, respectively, to the original Ikaria option exercise price. The expiration date of the options was not modified.

A summary of option activity under the assumed Ikaria 2007 stock option plan and the assumed Ikaria 2010 long term incentive plan for the nine months ended September 30, 2016, is presented below:



	Ikaria Equity Incentive Plans
	Options		Range of Exercise Price				Weighted Average Price		Weighted Average Remaining Contractual Life (in years)
Options outstanding as of December 31, 2015	113,709		$	0.26	-	17.92	$	8.93	5.2
Exercised	—
Forfeited	(25,542	)	0.26		-	17.92	8.13
Options outstanding as of September 30, 2016	88,167		$	7.77	-	17.92	$	9.16	4.6
Options vested and exercisable as of September 30, 2016	88,167		$	7.77	-	17.92	$	9.16	4.6

The intrinsic value of options outstanding, vested and exercisable as of September 30, 2016 was zero.

Stock-Based Compensation Expense, Net of Estimated Forfeitures

The following table summarizes the stock-based compensation expense by the unaudited condensed consolidated statement of operations line items for the three and nine months ended September 30, 2016 and 2015, respectively:



	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2016		2015		2016		2015
Research and development	$	203	$	32	$	656	$	274
General and administrative	576		405		1,492		970
Total stock-based compensation expense	$	779	$	437	$	2,148	$	1,244

Related-Party Transactions

9 Months Ended

Sep. 30, 2016

Related-Party Transactions

During the years ended December 31, 2014 and 2013, Ikaria was a related party of the Company. Included below and elsewhere in the financial statements are transactions and balances that relate to agreements entered into while Ikaria was a related party of the Company. Amendments to those agreements entered into during the year ended December 31, 2015, were entered into while the Company was no longer a related party.

Separation and Distribution Agreement

In connection with the Spin-Out, in February 2014, the Company and Ikaria entered into a separation and distribution agreement which set forth provisions relating to the separation of the Company’s business from Ikaria’s other businesses. The separation and distribution agreement described the assets and liabilities that remained with or were transferred to the Company and those that remained with or were transferred to Ikaria. The separation and distribution agreement provided for a full and complete release and discharge of all liabilities between Ikaria and the Company, except as expressly set forth in the agreement. The Company and Ikaria each agreed to indemnify, defend and hold harmless the other party and its subsidiaries, and each of their respective past and present directors, officers and employees, and each of their respective permitted successors and assigns, from any and all damages relating to, arising out of or resulting from, among other things, the Company’s business and certain additional specified liabilities or Ikaria’s business and certain additional specified liabilities, as applicable.

License Agreement

In February 2014, the Company entered into a cross-license, technology transfer and regulatory matters agreement with a subsidiary of Ikaria. Pursuant to the terms of the license agreement, Ikaria granted to the Company a fully paid-up, non-royalty-bearing, exclusive license under specified intellectual property rights controlled by Ikaria to engage in the development, manufacture and commercialization of nitric oxide, devices to deliver nitric oxide and related services for or in connection with out-patient, chronic treatment of patients who have PAH, PH-COPD or PH associated with idiopathic pulmonary fibrosis, or PH-IPF. Pursuant to the terms of the license agreement, the Company granted Ikaria a fully paid-up, non-royalty-bearing, exclusive license under specified intellectual property rights that the Company controls to engage in the development, manufacture and commercialization of products and services for or used in connection with the diagnosis, prevention or treatment, whether in- or out-patient, of certain conditions and diseases other than PAH, PH-COPD or PH-IPF and for the use of nitric oxide to treat or prevent conditions that are primarily managed in the hospital. The Company agreed that, during the term of the license agreement, it will not, without the prior written consent of Ikaria, grant a sublicense under any of the intellectual property licensed to the Company under the license agreement to any of its affiliates or any third party, in either case, that directly or indirectly competes with Ikaria’s nitric oxide business.

On July 27, 2015, the Company entered into an amendment to the license agreement to expand the scope of the Company’s license to allow the Company to develop its INOpulse platform for the treatment of three additional indications: chronic thromboembolic PH, or CTEPH, PH associated with sarcoidosis and PH associated with pulmonary edema from high altitude sickness. Subject to the terms set forth therein, the amendment to the license agreement also provides that the Company will pay Ikaria a royalty equal to 5% of net sales of any commercialized products for the three additional indications.

In November 2015, the Company entered into an amendment to its exclusive cross-license, technology transfer and regulatory matters agreement with Ikaria that included a royalty equal to 3% of net sales of any commercial products for PAH.

Agreements Not to Compete

In September 2013, October 2013 and February 2014, the Company and each of its subsidiaries entered into an agreement not to compete with a subsidiary of Ikaria, each of which was amended in July 2015, or, collectively, the agreements not to compete. Pursuant to the agreements not to compete, as amended, the Company and each of its subsidiaries agreed not to engage, anywhere in the world, in any manner, directly or indirectly, until the earlier of five years after the effective date of such agreement not to compete amendments or the date on which Ikaria and all of its subsidiaries are no longer engaged in such business as specified in the agreements.

Transition Services Agreement

In February 2014, the Company and Ikaria entered into a transition services agreement, or the TSA, pursuant to which Ikaria agreed to use commercially reasonable efforts to provide certain transition services to the Company, which services include management/executive, human resources, real estate, information technology, accounting, financial planning and analysis, legal, quality and regulatory support. Ikaria also agreed to use reasonable efforts to provide the Company with the use of office space at Ikaria’s headquarters in Hampton, New Jersey pursuant to the terms of the TSA. In July 2015, the Company entered into an amendment to the TSA advancing the termination date from February 9, 2016 to September 30, 2015. Concurrently, the Company also entered into a new lease agreement for its office space. In exchange for the services, beginning in February 2014, the Company was obligated to pay Ikaria monthly services fees in the amount of $772,000 plus out-of-pocket expenses and certain other expenses. Following the final payment in October 2015, the Company no longer had accrued expenses due to Ikaria in connection with the TSA.

At the time of the Spin-Out, the Company deposited the sum of $18.5 million, representing the aggregate of the $772,000 monthly service fees payable by the Company under the TSA, in escrow to guarantee payment of the monthly services fees by the Company. Pursuant to the July 2015 amendment, during October 2015, the Company received from escrow $3.3 million, which was equal to the amount it deposited to pay amounts owed to Ikaria under the TSA for the period from October 1, 2015 to February 9, 2016.

Effective as of January 1, 2015, the Company entered into a services agreement with Ikaria, or the 2015 Services Agreement, pursuant to which the Company had agreed to use commercially reasonable efforts to provide certain services to Ikaria, including services related to regulatory matters, drug and device safety, clinical operations, biometrics and scientific affairs. In connection with the execution of the 2015 Services Agreement, Ikaria paid the Company a one-time service fee in the amount of $916,666 and was obligated to pay the Company a service fee in the amount of $83,333 per month, subject to performance of the services. In July 2015, the Company entered into an amendment to the 2015 Services Agreement advancing the termination date from February 8, 2016 to September 30, 2015. In addition, pursuant to the 2015 Services Agreement, Ikaria had agreed to use commercially reasonable efforts to provide services to the Company, including information technology and servicing and upgrades of devices.

The following table summarizes the amounts recorded under the TSA and the 2015 Services Agreement for the three and nine months ended September 30, 2015:



(in millions)	Three Months Ended September 30, 2015			Nine Months Ended September 30, 2015
Expense in connection with the TSA	$	2.4		$	7.0
Other operating income in connection with the 2015 Services Agreement	(0.2		)	(1.7		)
Expense in connection with the 2015 Services Agreement	—			0.1

Supply Agreements

In February 2014, the Company entered into drug supply and device supply agreements with a subsidiary of Ikaria. Under these agreements, Ikaria agreed to use commercially reasonable efforts to supply inhaled nitric oxide and nitric oxide delivery devices for use in the Company’s clinical trials, and in the case of the drug supply agreement, the Company has agreed to purchase its clinical supply of inhaled nitric oxide from Ikaria. The Company also granted Ikaria a right of first negotiation in the event that the Company desired to enter into a commercial supply agreement with a third party for supply of nitric oxide for inhalation. The device supply agreement expired on February 9, 2015, and no amounts were due to Ikaria under that agreement as of March 31, 2015, or any subsequent periods.

In November 2015, the Company amended its drug supply agreement with Ikaria to secure future supply and pricing for cartridges and nitric oxide. Under the amended supply agreement, the Company paid Ikaria $6.6 million, $0.6 million of which was applied to outstanding amounts owed to Ikaria under the drug supply agreement. The remaining $6.0 million resulted in a prepayment to Ikaria in exchange for defined levels of cartridges and nitric oxide. The amendment to the agreement also fixes pricing for any additional cartridges or nitric oxide beyond the defined levels. Additionally, the amendment requires the Company to pay to Ikaria an additional $1.75 million upon successful completion of the initial PAH phase 3 clinical trial and a perpetual royalty calculated as 3% of PAH sales on a quarterly basis. Subsequent to the amendment, no amounts were due to Ikaria under the drug supply agreement.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings The Company periodically becomes subject to legal proceedings and claims arising in connection with its business. The ultimate legal and financial liability of the Company in respect to all proceedings, claims and lawsuits, pending or threatened, cannot be estimated with any certainty. As of this report, the Company is not aware of any proceeding, claim or litigation, pending or threatened, that could, individually or in the aggregate, have a material adverse effect on the Company’s business, operating results, financial condition and/or liquidity.

Net Loss Per Share	9 Months Ended
Net Loss Per Share	Sep. 30, 2016
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding during the period, as applicable. Diluted net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding, adjusted to reflect potentially dilutive securities (options) using the treasury stock method, except when the effect would be anti-dilutive. The Company reported a net loss for the three and nine months ended September 30, 2016 and 2015, therefore diluted net loss per share is the same as the basic net loss per share. As of September 30, 2016, the Company had 978,275 options to purchase shares and 321,821 restricted shares outstanding that have been excluded from the computation of diluted weighted average shares outstanding, because such securities had an anti-dilutive impact due to the loss reported.

Fair Value Measurements

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Fair Value Measurements

Assets and liabilities recorded at fair value on the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure the fair value. Level inputs are as follows:

· Level 1 — Values are based on unadjusted quoted prices for identical assets or liabilities in an active market which the company has the ability to access at the measurement date.

· Level 2 — Values are based on quoted market prices in markets where trading occurs infrequently or whose values are based on quoted prices of instruments with similar attributes in active markets.

· Level 3 — Values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement. These inputs reflect management’s own assumptions about the assumptions a market participant would use in pricing the asset.

The following table summarizes fair value measurements by level at September 30, 2016 for assets and liabilities measured at fair value on a recurring basis:



(Dollar amounts in thousands)	Level 1	Level 2		Level 3	Total
Marketable securities	—	$	7,230	—	$	7,230

The following table summarizes fair value measurements by level at December 31, 2015 for assets and liabilities measured at fair value on a recurring basis:



(Dollar amounts in thousands)	Level 1	Level 2		Level 3	Total
Marketable securities	—	$	17,807	—	$	17,807

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Restructuring Charges

9 Months Ended

Sep. 30, 2016

Restructuring and Related Activities [Abstract]

Restructuring Charges

On July 27, 2015, the Company announced that its PRESERVATION I clinical trial for its BCM product candidate did not meet its primary or secondary endpoints. Following these results, on September 11, 2015, the Board of Directors of the Company approved a staff reduction plan in order to reduce operating expenses and conserve cash resources, or the Restructuring. The Restructuring included a workforce reduction of approximately 20 people and was completed by the end of 2015.

The Company offered severance benefits to the affected employees, including cash severance payments. Each affected employee’s eligibility for the severance benefits was contingent upon such employee’s execution (and non-revocation) of a separation agreement, which includes a general release of claims against the Company.

The following table summarizes restructuring activities for the nine months ended September 30, 2016:



	Amounts
	(in thousands)
Accrual balance at December 31, 2015	$	969
Reversals (a)	(352		)
Cash payments	(393		)
Accrual balance at September 30, 2016 (b)	$	224

(a) Credited to general and administrative expense

(b) Included in Accrued expenses.

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements were prepared following the requirements of the Securities and Exchange Commission for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by accounting principles generally accepted in the United States of America, or U.S. GAAP, can be condensed or omitted. The Company operates in one reportable segment and solely within the United States. Accordingly, no segment or geographic information has been presented. The Company is responsible for the unaudited condensed consolidated financial statements. The condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair presentation of the Company’s financial position, results of operations, comprehensive loss and its cash flows for the periods presented. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements for the year ended December 31, 2015, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015. The results of operations for the three and nine months ended September 30, 2016 for the Company are not necessarily indicative of the results expected for the full year. The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of costs and expenses during the reporting period, including accrued expenses, accrued research and development expenses, stock-based compensation, and income taxes. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity date of three months or less to be cash equivalents. All investments with maturities of greater than three months from date of purchase are classified as available-for-sale marketable securities.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for its stock-based compensation in accordance with Accounting Standards Codification, or ASC, 718 Compensation- Stock Compensation, which establishes accounting for share-based awards, including stock options and restricted stock, exchanged for services and requires companies to expense the estimated fair value of these awards over the requisite service period. The Company recognizes stock-based compensation expense in operations based on the fair value of the award on the date of the grant. The resulting compensation expense is recognized on a straight-line basis over the requisite service period or sooner if the awards immediately vest. The Company determines the fair value of stock options issued using a Black-Scholes-Merton option pricing model. Certain assumptions used in the model include expected volatility, dividend yield, risk-free interest rate, and expected term. For restricted stock, the fair value is the closing market price per share on the grant date. See Note 6 - Stock-Based Compensation for a description of these assumptions.
Income Taxes	Income Taxes Prior to its conversion to a Delaware corporation in February 2015, the Company was a Delaware limited liability company, or LLC, that passed through income and losses to its members for U.S. federal and state income tax purposes. As a result of its conversion to a Delaware corporation, the Company recognized deferred income taxes through income tax expense related to temporary differences that existed as of the date of its tax status change. The Company uses the asset and liability approach to account for income taxes as required by ASC 740, Income Taxes, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Valuation allowances are provided when necessary to reduce deferred tax assets to the amount expected to be realized, on a more likely than not basis. The Company recognizes the benefit of an uncertain tax position that it has taken or expects to take on income tax returns it files if such tax position is more likely than not to be sustained on examination by the taxing authorities, based on the technical merits of the position. These tax benefits are measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate resolution. The Company’s estimated tax rate for 2016 is expected to be zero because the Company expects to generate additional losses and currently has a full valuation allowance. The deferred tax assets balance before valuation allowance as of September 30, 2016 was approximately $47.7 million. The increase in deferred tax assets in the three and nine months ended September 30, 2016 is principally due to the year-to-date loss, adjusted for nondeductible items including stock compensation expense related to the Company’s equity incentive plan, the nondeductible portion of orphan drug costs, and orphan drug federal income tax credits. The valuation allowance is required until the Company has sufficient positive evidence of taxable income necessary to support realization of its deferred tax assets. The Company did not have material uncertain tax positions as of September 30, 2016.
Marketable Securities	Marketable Securities The Company’s marketable securities consist of federally insured certificates of deposit classified as available-for-sale that are recorded at amortized cost, which approximates fair value, and corporate or agency bonds classified as available-for-sale that are recorded at fair value. Unrealized gains and losses are reported as accumulated other comprehensive (loss) income, except for losses from impairments which are determined to be other-than-temporary. Realized gains and losses, and declines in value judged to be other-than-temporary on available-for-sale securities are included in the determination of net loss and are included in interest income, at which time the average cost basis of these securities are adjusted to fair value. Fair values are based on quoted market prices at the reporting date. Interest on available-for-sale securities are included in interest income.
Research and Development Expense	Research and Development Expense Research and development costs are expensed as incurred. These expenses include the costs of the Company’s proprietary research and development efforts, as well as costs incurred in connection with certain licensing arrangements. Upfront and milestone payments made to third parties in connection with research and development collaborations are expensed as incurred up to the point of regulatory approval. Payments made to third parties upon or subsequent to regulatory approval are capitalized and amortized over the remaining useful life of the related product. The Company also expenses the cost of purchased technology and equipment in the period of purchase if it believes that the technology or equipment has not demonstrated technological feasibility and it does not have an alternative future use. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and are recognized as research and development expense as the related goods are delivered or the related services are performed.
New Accounting Pronouncements	New Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, “Revenue from Contracts with Customers,” which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2018. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is assessing ASU 2014-09’s impact and will adopt it when effective. In August 2014, the Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, or ASU, 2014-15, “Presentation of Financial Statements - Going Concern: Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern.” This guidance clarifies that an entity’s management should evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued. The amendments in this update are effective for annual reporting periods ending after December 15, 2016, and annual and interim periods thereafter, and early application is permitted. The Company is assessing ASU 2014-15’s impact and will adopt it when effective. In January 2016, the FASB issued ASU 2016-01, "Financial Instruments - Overall - Recognition and Measurement of Financial Assets and Financial Liabilities," which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. This standard will be effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company is assessing ASU 2016-01’s impact and will adopt it when effective. In February 2016, the FASB issued ASU 2016-02, "Leases," which is intended to improve financial reporting about leasing transactions. This standard requires a lessee to record on the balance sheet the assets and liabilities for the rights and obligations created by lease terms of more than 12 months. This standard will be effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company is assessing ASU 2016-02’s impact and will adopt it when effective. In March 2016, the FASB issued ASU 2016-09, "Compensation - Stock Compensation - Improvements to Employee Share-Based Payment Accounting" which provides for simplification of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. This standard will be effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The Company is assessing ASU 2016-09’s impact and will adopt it when effective. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows: Clarification of Certain Cash Receipts and Cash Payments”, which eliminates the diversity in practice related to the classification of certain cash receipts and payments in the statement of cash flows, by adding or clarifying guidance on eight specific cash flow issues. ASU 2016-15 is effective for annual and interim reporting periods beginning after December 15, 2017 and early adoption is permitted. ASU 2016-15 provides for retrospective application for all periods presented. The Company is assessing ASU 2016-15’s impact and will adopt it when effective.

- Definition

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.

+ References + Details

Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2016

Marketable Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation

The Company considers all of its investments to be available-for-sale. Marketable securities as of September 30, 2016 consist of the following (in thousands):



	Amortized Cost	Gross Unrealized Gains	Gross Unrealized Losses		Fair Value
Certificates of deposit	5,274	—	—		5,274
Corporate bonds	1,957	—	(1	)	1,956
Total	7,231	—	(1	)	7,230

Marketable securities as of December 31, 2015, consist of the following (in thousands):



	Amortized Cost	Gross Unrealized Gains	Gross Unrealized Losses		Fair Value
Certificates of deposit	10,140	—	—		10,140
Corporate bonds	4,938	—	(11	)	4,927
Agency bonds	2,748	—	(8	)	2,740
Total	17,826	—	(19	)	17,807

Available-for-sale Securities

Maturities of marketable securities classified as available-for-sale were as follows at September 30, 2016 and December 31, 2015 (in thousands):



	September 30, 2016	December 31, 2015
Due within one year	6,533	10,230
Due after one year through two years	697	7,577
	7,230	17,807

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2016

Stock-Based Compensation

Assumptions used in estimating the fair value of options issued

The following are the weighted average assumptions used in estimating the fair value of stock options issued during the nine months ended September 30, 2016 and 2015:



	Nine Months Ended September 30, 2016		Nine Months Ended September 30, 2015
Valuation assumptions:
Risk-free rate	1.34	%	1.60	%
Expected volatility	81.8	%	79.2	%
Expected term (years)	6.1		6.1
Dividend yield	—		—

Summary of option activity



	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2016		2015		2016		2015
Research and development	$	203	$	32	$	656	$	274
General and administrative	576		405		1,492		970
Total stock-based compensation expense	$	779	$	437	$	2,148	$	1,244

Summary of restricted stock activity

A summary of restricted stock activity under the 2015 Plan for the nine months ended September 30, 2016 is presented below:



	Shares		Weighted Average Fair Value		Aggregate Grant Date Fair Value (in millions)			Weighted Average Remaining Contractual Life (in years)
Restricted stock outstanding as of December 31, 2015	77,793		$	3.99	$	0.3		0.7
Granted	519,871		2.40		1.2
Released	(251,842	)	2.86		(0.7		)
Forfeited	(24,001	)	3.69		(0.1		)
Restricted stock outstanding as of September 30, 2016	321,821		$	2.33	$	0.7		0.3

Summary of stock-based compensation expense by the condensed consolidated statement of operations line item

A summary of option activity under the assumed Ikaria 2007 stock option plan and the assumed Ikaria 2010 long term incentive plan for the nine months ended September 30, 2016, is presented below:



	Ikaria Equity Incentive Plans
	Options		Range of Exercise Price				Weighted Average Price		Weighted Average Remaining Contractual Life (in years)
Options outstanding as of December 31, 2015	113,709		$	0.26	-	17.92	$	8.93	5.2
Exercised	—
Forfeited	(25,542	)	0.26		-	17.92	8.13
Options outstanding as of September 30, 2016	88,167		$	7.77	-	17.92	$	9.16	4.6
Options vested and exercisable as of September 30, 2016	88,167		$	7.77	-	17.92	$	9.16	4.6

Bellerophon 2015 And 2014 Equity Incentive Plan

Stock-Based Compensation

Summary of option activity

A summary of stock option activity under the 2015 Plan and 2014 Plan for the nine months ended September 30, 2016 is presented below:



	Options		Range of Exercise Price				Weighted Average Price		Weighted Average Remaining Contractual Life (in years)
Options outstanding as of December 31, 2015	705,180		$	4.12	-	13.28	$	12.08	8.7
Granted	230,000		1.40		-	2.30	2.17
Exercised	—
Forfeited	(45,072	)	10.22		-	13.28	11.68
Options outstanding as of September 30, 2016	890,108		$	1.40	-	13.28	$	9.54	8.3
Options vested and exercisable as of September 30, 2016	334,025		$	4.12	-	13.28	$	12.58	7.8

Related-Party Transactions (Tables)

9 Months Ended

Sep. 30, 2016

Schedule of related party transactions

The following table summarizes the amounts recorded under the TSA and the 2015 Services Agreement for the three and nine months ended September 30, 2015:



(in millions)	Three Months Ended September 30, 2015			Nine Months Ended September 30, 2015
Expense in connection with the TSA	$	2.4		$	7.0
Other operating income in connection with the 2015 Services Agreement	(0.2		)	(1.7		)
Expense in connection with the 2015 Services Agreement	—			0.1

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Summary of fair value measurements by level

The following table summarizes fair value measurements by level at September 30, 2016 for assets and liabilities measured at fair value on a recurring basis:



(Dollar amounts in thousands)	Level 1	Level 2		Level 3	Total
Marketable securities	—	$	7,230	—	$	7,230

The following table summarizes fair value measurements by level at December 31, 2015 for assets and liabilities measured at fair value on a recurring basis:



(Dollar amounts in thousands)	Level 1	Level 2		Level 3	Total
Marketable securities	—	$	17,807	—	$	17,807

Restructuring Charges (Tables)

9 Months Ended

Sep. 30, 2016

Restructuring and Related Activities [Abstract]

Summary of restructuring activities

The following table summarizes restructuring activities for the nine months ended September 30, 2016:



	Amounts
	(in thousands)
Accrual balance at December 31, 2015	$	969
Reversals (a)	(352		)
Cash payments	(393		)
Accrual balance at September 30, 2016 (b)	$	224

(a) Credited to general and administrative expense

(b) Included in Accrued expenses.

Organization and Nature of the Business - Narrative (Details)			9 Months Ended		12 Months Ended
	Feb. 19, 2015 USD ($) $ / shares shares	Feb. 02, 2015	Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($)	Dec. 31, 2013 integer	May 27, 2016 USD ($)	May 23, 2016 USD ($)
Organization and Nature of the Business [Line Items]
Stock split ratio		0.079836
Completed sale (in shares) \| shares			973,024
Maximum securities shelf offering							$ 30,000,000.0
Proceeds from ATM Offering, gross			$ 2,200,000
Proceeds from ATM Offering, net			$ 2,048,000	$ 0
IPO
Organization and Nature of the Business [Line Items]
Completed sale (in shares) \| shares	5,000,000
Price to the public (in dollars per share) \| $ / shares	$ 12.00
Net proceeds to the Company	$ 51,900,000
Underwriting discounts and commissions	4,200,000
Offering costs deducted	$ 3,900,000
Share Distribution
Organization and Nature of the Business [Line Items]
Common stock, value, subscriptions						$ 5,700,000.0
Ikaria
Organization and Nature of the Business [Line Items]
Number of operating segments \| integer					2

Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015	Sep. 30, 2016 USD ($) integer	Sep. 30, 2015	Dec. 31, 2016
Valuation Allowance [Line Items]
Number of reportable segments \| integer			1
Effective tax rate (as a percent)	0.00%	0.00%	0.00%	0.00%
Deferred tax assets before valuation allowance \| $	$ 47.7		$ 47.7
Scenario, Forecast
Valuation Allowance [Line Items]
Effective tax rate (as a percent)					0.00%

Liquidity - Narrative (Details) - USD ($)		9 Months Ended
Liquidity - Narrative (Details) - USD ($)	Feb. 19, 2015	Sep. 30, 2016	Sep. 30, 2015	May 27, 2016	Dec. 31, 2015	Dec. 31, 2014
Liquidity [Line Items]
Completed sale (in shares)		973,024
Proceeds from ATM Offering, gross		$ 2,200,000
Proceeds from ATM Offering, net		2,048,000	$ 0
Cash and cash equivalents		3,930,000	$ 23,908,000		$ 6,260,000	$ 16,815,000
Marketable securities		7,230,000			17,807,000
IPO
Liquidity [Line Items]
Net proceeds to the Company	$ 51,900,000
Underwriting discounts and commissions	4,200,000
Offering costs deducted	$ 3,900,000
Completed sale (in shares)	5,000,000
Share Distribution
Liquidity [Line Items]
Common stock, value, subscriptions				$ 5,700,000.0
Committed Equity Funding
Liquidity [Line Items]
Common stock, value, subscriptions		4,000,000.0			$ 20,000,000
Commitment letter maximum ownership percentage (more than)					19.90%
Committed Equity Funding First Two Draw Downs
Liquidity [Line Items]
Common stock, value, subscriptions					$ 2,000,000
Drug supply agreement \| Affiliated Entity
Liquidity [Line Items]
Prepaid research and development		$ 8,600,000			$ 11,300,000

Marketable Securities - (Schedule of Available-for-sale Securities Reconciliation) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 7,231	$ 17,826
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(19)
Fair Value	7,230	17,807
Certificates of deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,274	10,140
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	5,274	10,140
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,957	4,938
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(11)
Fair Value	$ 1,956	4,927
Agency bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		2,748
Gross Unrealized Gains		0
Gross Unrealized Losses		(8)
Fair Value		$ 2,740

Marketable Securities - (Schedule of Investments in Debt and Marketable Equity Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Marketable Securities [Abstract]
Due within one year	$ 6,533	$ 10,230
Due after one year through two years	697	7,577
Total	$ 7,230	$ 17,807

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)	0.00%	0.00%	0.00%	0.00%
Expected change to unrecognized tax benefit liability in next twelve months	$ 0		$ 0

Stock-Based Compensation - Narrative (Details) - USD ($)		1 Months Ended	9 Months Ended
	Feb. 12, 2014	Feb. 28, 2014	Sep. 30, 2016	Sep. 30, 2015
Bellerophon Equity Incentive Plans
Stock-Based Compensation
Unrecognized compensation expense			$ 2,700,000
Weighted-average period unrecognized compensation expense is to be recognized			1 year 10 months 24 days
Tax benefit recognized related to stock-based compensation expense			$ 0	$ 0
Weighted average grant-date fair value of options issued (in dollars per share)			$ 1.52	$ 6.55
Number of options granted (in shares)			230,000
Ikaria Equity Incentive Plans prior to February 12, 2014
Stock-Based Compensation
Number of options granted (in shares)		618,212
Allocation percentage of post Spin-Out estimated fair value of Ikaria to original option exercise price (as a percent)	85.00%
Allocation percentage of post Spin-Out estimated fair value of the Company to original option exercise price (as a percent)	15.00%
2014 Equity Incentive Plan
Stock-Based Compensation
Vesting period			4 years
2014 Equity Incentive Plan \| First anniversary
Stock-Based Compensation
Vesting percentage			25.00%
2014 Equity Incentive Plan \| Third anniversary
Stock-Based Compensation
Vesting percentage			25.00%
2014 Equity Incentive Plan \| Second anniversary
Stock-Based Compensation
Vesting percentage			50.00%
2015 Equity Incentive Plan \| First tranche
Stock-Based Compensation
Vesting period			3 years
2015 Equity Incentive Plan \| Second tranche
Stock-Based Compensation
Vesting period			4 years

Stock-Based Compensation - (Summary of Fair Value of Options Issued) (Details) - Bellerophon Equity Incentive Plans	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free rate (as a percent)	1.34%	1.60%
Expected volatility (as a percent)	81.80%	79.20%
Expected term (years)	6 years 1 month 6 days	6 years 1 month 6 days
Dividend yield (as a percent)	0.00%	0.00%

Stock-Based Compensation - (Summary of Option Activity) (Details) - USD ($)	1 Months Ended	9 Months Ended	12 Months Ended
	Feb. 28, 2014	Sep. 30, 2016	Dec. 31, 2015
Ikaria Equity Incentive Plans prior to February 12, 2014
Shares
Options outstanding as of beginning of period (in shares)		113,709
Granted (in shares)	618,212
Exercise of options (in shares)		0
Forfeited (in shares)		(25,542)
Options outstanding as of end of period (in shares)		88,167	113,709
Options vested and exercisable (in shares)		88,167
Exercise Price
Options outstanding, Exercise Price, minimum (in dollars per share)			$ 0.26
Options outstanding, Exercise Price, maximum (in dollars per share)			17.92
Weighted Average Price
Options outstanding as of beginning of period, Weighted Average Price (in dollars per share)		$ 8.93
Options forfeited, Weighted Average Price (in dollars per share)		8.13
Options outstanding as of end of period, Weighted Average Price (in dollars per share)		9.16	$ 8.93
Options vested and exercisable, Weighted Average Price (in dollars per share)		$ 9.16
Weighted Average Remaining Contractual Life (in years)
Options outstanding, Weighted Average Remaining Contractual Life (in years)		4 years 7 months 6 days	5 years 2 months 12 days
Options vested and exercisable as of September 30, 2016		4 years 7 months 6 days
Intrinsic Value
Options outstanding, intrinsic value (in dollars per share)		$ 0
Options exercisable, intrinsic value (in dollars per share)		0
Options vested, intrinsic value (in dollars per share)		$ 0
Ikaria Equity Incentive Plans prior to February 12, 2014 \| Minimum
Exercise Price
Options outstanding, Exercise Price, minimum (in dollars per share)		$ 7.77
Options forfeited, Exercise Price (in dollars per share)		0.26
Options vested and exercisable, Exercise Price (in dollars per share)		7.77
Ikaria Equity Incentive Plans prior to February 12, 2014 \| Maximum
Exercise Price
Options outstanding, Exercise Price, maximum (in dollars per share)		17.92
Options forfeited, Exercise Price (in dollars per share)		17.92
Options vested and exercisable, Exercise Price (in dollars per share)		$ 17.92
Bellerophon Equity Incentive Plans
Shares
Options outstanding as of beginning of period (in shares)		705,180
Granted (in shares)		230,000
Exercise of options (in shares)		0
Forfeited (in shares)		(45,072)
Options outstanding as of end of period (in shares)		890,108	705,180
Options vested and exercisable (in shares)		334,025
Weighted Average Price
Options outstanding as of beginning of period, Weighted Average Price (in dollars per share)		$ 12.08
Options granted, Weighted Average Price (in dollars per share)		2.17
Options forfeited, Weighted Average Price (in dollars per share)		11.68
Options outstanding as of end of period, Weighted Average Price (in dollars per share)		9.54	$ 12.08
Options vested and exercisable, Weighted Average Price (in dollars per share)		$ 12.58
Weighted Average Remaining Contractual Life (in years)
Options outstanding, Weighted Average Remaining Contractual Life (in years)		8 years 3 months 18 days	8 years 8 months 12 days
Options vested and exercisable as of September 30, 2016		7 years 9 months 18 days
Bellerophon Equity Incentive Plans \| Minimum
Exercise Price
Options outstanding, Exercise Price, minimum (in dollars per share)		$ 1.40	$ 4.12
Options granted, Exercise Price (in dollars per share)		1.40
Options forfeited, Exercise Price (in dollars per share)		10.22
Options vested and exercisable, Exercise Price (in dollars per share)		4.12
Bellerophon Equity Incentive Plans \| Maximum
Exercise Price
Options outstanding, Exercise Price, maximum (in dollars per share)		13.28	$ 13.28
Options granted, Exercise Price (in dollars per share)		2.30
Options forfeited, Exercise Price (in dollars per share)		13.28
Options vested and exercisable, Exercise Price (in dollars per share)		$ 13.28

Stock-Based Compensation - (Summary of Restricted Stock Activity) (Details) - 2015 Equity Incentive Plan - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Restricted stock
Restricted stock outstanding, beginning of period (in shares)	77,793
Restricted stock granted (in shares)	519,871
Restricted stock released (in shares)	(251,842)
Restricted stock forfeited (in shares)	(24,001)
Restricted stock outstanding, end of period (in shares)	321,821	77,793
Restricted stock weighted average fair value per share
Restricted stock beginning of period, weighted average fair value (per share)	$ 3.99
Restricted stock granted, weighted average fair value (per share)	2.40
Restricted stock released, weighted average fair value (per share)	2.86
Restricted stock forfeited, weighted average fair value (per share)	3.69
Restricted stock end of period, weighted average fair value (per share)	$ 2.33	$ 3.99
Restricted stock aggregate grant date fair value
Restricted stock beginning of period, aggregate grant date fair value	$ 0.3
Restricted stock granted, aggregate grant date fair value	1.2
Restricted stock released, aggregate grant date fair value	(0.7)
Restricted stock forfeited, aggregate grant date fair value	(0.1)
Restricted stock end of period, aggregate grant date fair value	$ 0.7	$ 0.3
Weighted average remaining contractual life (in years)
Restricted stock, weighted average remaining contractual life (in years)	3 months 24 days	8 months 12 days

Stock-Based Compensation - (Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Stock-based compensation expense by condensed consolidated statement of operations and comprehensive loss line item
Total stock-based compensation expense	$ 779	$ 437	$ 2,148	$ 1,244
Charged to research and development expense
Stock-based compensation expense by condensed consolidated statement of operations and comprehensive loss line item
Total stock-based compensation expense	203	32	656	274
Charged to general and administrative expense
Stock-based compensation expense by condensed consolidated statement of operations and comprehensive loss line item
Total stock-based compensation expense	$ 576	$ 405	$ 1,492	$ 970

Related-Party Transactions - Narrative (Details) - USD ($)			1 Months Ended
	Jul. 27, 2015	Feb. 12, 2014	Nov. 30, 2015	Oct. 31, 2015	Jul. 31, 2015	Jan. 31, 2015	Feb. 28, 2014	Sep. 30, 2016	Dec. 31, 2015	Mar. 31, 2015	Jan. 01, 2015
Related Party Transaction [Line Items]
Amount deposited in escrow		$ 18,500,000
Escrow deposit received after termination of agreement				$ 3,300,000
Accrued expenses and amounts due								$ 166,000	$ 148,000
Ikaria \| License Agreement
Related Party Transaction [Line Items]
Royalty to related party (as a percent)	5.00%
Perpetual royalty (as a percent)			3.00%
Ikaria \| Agreements Not to Compete
Related Party Transaction [Line Items]
Term of agreement					5 years
Ikaria \| Transition services agreement (TSA)
Related Party Transaction [Line Items]
Monthly service fee							$ 772,000
Ikaria \| Services agreement entered into January 2015
Related Party Transaction [Line Items]
Service fee						$ 916,666
Monthly additional service fee											$ 83,333
Ikaria \| Device supply agreement
Related Party Transaction [Line Items]
Accrued expenses and amounts due										$ 0
Affiliated Entity \| Drug supply agreement
Related Party Transaction [Line Items]
Perpetual royalty (as a percent)			3.00%
Accrued expenses and amounts due			$ 600,000
Payment to related party			6,600,000
Prepaid research and development, current			6,000,000
Amount to be incurred for certain services provided by Ikaria			$ 1,750,000

Related-Party Transaction - (Schedule of Related Party Transactions) (Details) - Ikaria - USD ($)	1 Months Ended	3 Months Ended	9 Months Ended
	Jan. 31, 2015	Sep. 30, 2015	Sep. 30, 2015
Transition services agreement (TSA)
Related Party Transaction [Line Items]
Expense in connection with the TSA		$ 2,400,000	$ 7,000,000
Services agreement entered into January 2015
Related Party Transaction [Line Items]
Other operating income in connection with the 2015 Services Agreement	$ (916,666)
Expense in connection with the 2015 Services Agreement		0	100,000
Other Operating Income \| Services agreement entered into January 2015
Related Party Transaction [Line Items]
Other operating income in connection with the 2015 Services Agreement		$ (200,000)	$ (1,700,000)

Net Loss Per Share - Narrative (Details)	9 Months Ended
Net Loss Per Share - Narrative (Details)	Sep. 30, 2016 shares
Options to purchase units outstanding
Net Loss Per Share
Antidilutive securities excluded from computation of weighted average units outstanding	978,275
Restricted stock outstanding
Net Loss Per Share
Antidilutive securities excluded from computation of weighted average units outstanding	321,821

Fair Value Measurements (Details) - Recurring - Marketable Securities - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	$ 7,230	$ 17,807
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	7,230	17,807
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	$ 0	$ 0

Restructuring Charges - (Summary of Restructuring Activities) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($)
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 969
Cash payments	(393)
Restructuring reserve, ending balance	224
General and Administrative Expense
Restructuring Reserve [Roll Forward]
Reversals	$ (352)

Condensed Consolidated Statements of Changes in Stockholders'/Members Equity (Parenthetical) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($)
Statement of Stockholders' Equity [Abstract]
Underwriting commissions and offering expenses incurred	$ 149

Restructuring Charges - Narrative (Details)	3 Months Ended
Restructuring Charges - Narrative (Details)	Dec. 31, 2015 person
Employee Severance
Restructuring Cost and Reserve [Line Items]
Number of positions to be eliminated	20