MannKind (MNKD) 10-Q 6 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 13, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	MNKD
Entity Registrant Name	MANNKIND CORP
Entity Central Index Key	0000899460
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Entity File Number	000-50865
Entity Tax Identification Number	13-3607736
Entity Address, Address Line One	30930 Russell Ranch Road
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Westlake Village
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	91362
City Area Code	(818)
Local Phone Number	661-5000
Entity Common Stock, Shares Outstanding		213,137,730
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common Stock, par value $0.01 per share
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 38,868,000	$ 29,906,000
Restricted cash	316,000	316,000
Short-term investments	0	19,978,000
Accounts receivable, net	5,032,000	3,513,000
Inventory	3,231,000	4,155,000
Prepaid expenses and other current assets	1,901,000	2,889,000
Total current assets	49,348,000	60,757,000
Property and equipment, net	26,517,000	26,778,000
Other assets	4,347,000	6,190,000
Total assets	80,212,000	93,725,000
Current liabilities:
Accounts payable	6,731,000	4,789,000
Accrued expenses and other current liabilities	18,326,000	15,904,000
Short-term note payable	5,101,000	5,028,000
Deferred revenue — current	30,840,000	32,503,000
Recognized loss on purchase commitments — current	7,250,000	7,394,000
Total current liabilities	68,248,000	65,618,000
Promissory notes	70,022,000	70,020,000
Accrued interest — promissory notes	3,259,000	2,002,000
Long-term Midcap credit facility	38,893,000	38,851,000
Senior convertible notes	5,000,000	5,000,000
Recognized loss on purchase commitments — long term	82,987,000	84,639,000
Operating lease liability	2,155,000	2,514,000
Deferred revenue — long term	1,772,000	8,344,000
Milestone rights liability	5,926,000	7,263,000
Total liabilities	278,262,000	284,251,000
Commitments and contingencies
Stockholders' deficit:
Undesignated preferred stock, $0.01 par value — 10,000,000 shares authorized; no shares issued or outstanding as of March 31, 2020 and December 31, 2019
Common stock, $0.01 par value - 280,000,000 shares authorized, 213,137,684 and 211,787,573 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	2,131,000	2,118,000
Additional paid-in capital	2,801,044,000	2,799,278,000
Accumulated other comprehensive loss		(19,000)
Accumulated deficit	(3,001,225,000)	(2,991,903,000)
Total stockholders' deficit	(198,050,000)	(190,526,000)
Total liabilities and stockholders' deficit	$ 80,212,000	$ 93,725,000

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Undesignated preferred stock, par value	$ 0.01	$ 0.01
Undesignated preferred stock, shares authorized	10,000,000	10,000,000
Undesignated preferred stock, shares issued	0	0
Undesignated preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	280,000,000	280,000,000
Common stock, shares issued	213,137,684	211,787,573
Common stock, shares outstanding	213,137,684	211,787,573

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues:
Total revenues	$ 16,235	$ 17,448
Expenses:
Cost of goods sold	4,164	4,020
Research and development	1,755	1,667
Selling, general and administrative	14,350	25,673
Impairment of commitment asset	1,521
Gain on foreign currency translation	(1,796)	(1,935)
Total expenses	23,356	30,962
Loss from operations	(7,121)	(13,514)
Other (expense) income:
Interest income	133	318
Interest expense on notes	(1,071)	(593)
Interest expense on promissory notes	(1,259)	(1,080)
Other expense	(4)	(14)
Total other expense	(2,201)	(1,369)
Loss before provision for income taxes	(9,322)	(14,883)
Net loss	$ (9,322)	$ (14,883)
Net loss per share - basic and diluted	$ (0.04)	$ (0.08)
Shares used to compute basic and diluted net loss per share	212,467	187,434
Commercial product sales
Revenues:
Total revenues	$ 8,000	$ 5,076
Collaborations and services
Revenues:
Total revenues	8,235	12,372
Expenses:
Cost of revenue	$ 3,362	$ 1,537

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (9,322)	$ (14,883)
Other comprehensive loss:
Cumulative translation loss	(19)
Comprehensive loss	$ (9,341)	$ (14,883)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Deficit - USD ($) shares in Thousands, $ in Thousands	Total	At-the-market Offering	Senior Convertible Notes	Common Stock	Common StockAt-the-market Offering	Common StockSenior Convertible Notes	Additional Paid-in Capital	Additional Paid-in CapitalAt-the-market Offering	Additional Paid-in CapitalSenior Convertible Notes	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance at Dec. 31, 2018	$ (175,082)			$ 1,870			$ 2,763,067			$ (19)	$ (2,940,000)
Beginning Balance (in shares) at Dec. 31, 2018				187,030
Net issuance of common stock associated with stock options and restricted stock units	2			$ 1			1
Net issuance of common stock associated with stock options and restricted stock units (in shares)				66
Issuance of common stock under Employee Stock Purchase Plan	317			$ 3			314
Issuance of common stock under Employee Stock Purchase Plan (in shares)				296
Stock-based compensation expense	999						999
Issuance of common stock pursuant to conversion notes			$ 538			$ 4			$ 534
Issuance of common stock pursuant to conversion notes (in shares)						386
Restricted stock unit award	105						105
Net loss	(14,883)										(14,883)
Ending Balance at Mar. 31, 2019	(188,004)			$ 1,878			2,765,020			(19)	(2,954,883)
Ending Balance (in shares) at Mar. 31, 2019				187,778
Beginning Balance at Dec. 31, 2019	(190,526)			$ 2,118			2,799,278			(19)	(2,991,903)
Beginning Balance (in shares) at Dec. 31, 2019				211,788
Net issuance of common stock associated with stock options and restricted stock units	(317)			$ 5			(322)
Net issuance of common stock associated with stock options and restricted stock units (in shares)				504
Issuance of common stock under Employee Stock Purchase Plan	318			$ 3			315
Issuance of common stock under Employee Stock Purchase Plan (in shares)				334
Stock-based compensation expense	1,128						1,128
Issuance of common stock associated with debt interest payment	144			$ 1			143
Issuance of common stock associated with debt interest payment (in shares)				99
Issuance of common stock		$ 522			$ 4			$ 518
Issuance of common stock (in shares)					413
Issuance cost associated with at-the-market offering	(16)						(16)
Cumulative translation loss	19									$ 19
Net loss	(9,322)										(9,322)
Ending Balance at Mar. 31, 2020	$ (198,050)			$ 2,131			$ 2,801,044				$ (3,001,225)
Ending Balance (in shares) at Mar. 31, 2020				213,138

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (9,322,000)	$ (14,883,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Impairment of commitment asset	1,521,000
Stock-based compensation expense	1,128,000	999,000
Depreciation, amortization and accretion	538,000	367,000
Amortization of right-of-use assets	282,000	395,000
Gain on foreign currency translation	(1,796,000)	(1,935,000)
Interest expense on promissory notes	1,257,000	1,134,000
Write-off of inventory	496,000	0
Other, net	19,000	104,000
Changes in operating assets and liabilities:
Accounts receivable, net	(1,661,000)	258,000
Inventory	428,000	(123,000)
Prepaid expenses and other current assets	988,000	164,000
Other assets	40,000	(340,000)
Accounts payable	1,942,000	1,599,000
Accrued expenses and other current liabilities	1,880,000	2,336,000
Deferred revenue	(8,235,000)	686,000
Operating lease liabilities	(724,000)	(395,000)
Recognized loss on purchase commitments		(1,963,000)
Net cash used in operating activities	(11,219,000)	(11,597,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(150,000)	(269,000)
Purchase of treasury bills		(24,764,000)
Proceeds from sale of treasury bills	20,000,000
Net cash provided by (used in) investing activities	19,850,000	(25,033,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Exercise of stock options	8,000
Payment of employment taxes related to vested restricted stock units	(325,000)
Other		3,000
Net cash provided by financing activities	331,000	3,000
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	8,962,000	(36,627,000)
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING OF PERIOD	30,222,000	71,684,000
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH, END OF PERIOD	39,184,000	35,057,000
SUPPLEMENTAL CASH FLOWS DISCLOSURES:
Interest paid in cash, net of amounts capitalized	885,000
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Common stock issuance to settle employee stock purchase plan liability	318,000	317,000
Payment of interest on senior convertible notes through common stock issuance	144,000	534,000
Non-cash construction in progress and property and equipment	32,000	246,000
Addition of right-of-use assets upon adoption of new lease guidance		$ 5,192,000
At The Market Issuance
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from at-the-market offering	668,000
Issuance costs associated with at-the-market offering	$ 20,000

Description of Business and Sig

Description of Business and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Description of Business and Significant Accounting Policies	1. Description of Business and Significant Accounting Policies The accompanying unaudited condensed consolidated financial statements of MannKind Corporation and its subsidiaries (“MannKind,” the “Company,” “we” or “us”), have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (the “SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. The information included in this quarterly report on Form 10-Q should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s annual report on Form 10-K for the fiscal year ended December 31, 2019 filed with the SEC on February 25, 2020 (the “Annual Report”). In the opinion of management, all adjustments, consisting only of normal, recurring adjustments, considered necessary for a fair presentation of the results of these interim periods have been included. The results of operations for the three months ended March 31, 2020 may not be indicative of the results that may be expected for the full year. Financial Statement Estimates — The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates or assumptions. Management considers many factors in selecting appropriate financial accounting policies, and in developing the estimates and assumptions that are used in the preparation of the financial statements. Management must apply significant judgment in this process and the threat of the COVID-19 pandemic has increased the level of judgment used by management in developing these estimates and assumptions. The COVID-19 pandemic continues to rapidly evolve and the ultimate impact of the COVID-19 pandemic is highly uncertain and subject to change. These effects could have a material impact on the estimates and assumptions used in the preparation of the accompanying condensed consolidated financial statements. The more significant estimates include revenue recognition and gross-to-net adjustments, assessing long-lived assets for impairment, clinical trial expenses, inventory costing and recoverability, recognized loss on purchase commitment, milestone rights liability, stock-based compensation and the determination of the provision for income taxes and corresponding deferred tax assets and liabilities, and the valuation allowance recorded against net deferred tax assets. Business — The Company is a biopharmaceutical company focused on the development and commercialization of inhaled therapeutic products for diabetes and orphan lung diseases, such as pulmonary arterial hypertension. The Company’s only approved product, Afrezza (insulin human) Inhalation Powder, is an ultra rapid-acting inhaled insulin that was approved by the U.S. Food and Drug Administration (the “FDA”) in June 2014 to improve glycemic control in adults with diabetes. Afrezza became available by prescription in United States retail pharmacies in February 2015. Currently, the Company promotes Afrezza to endocrinologists and certain high-prescribing primary care physicians in the United States through its specialty sales force. The Company’s partner in Brazil, Biomm S.A., commenced commercialization of Afrezza in January 2020. The Company’s partners in India and Australia are preparing for regulatory submissions and have not yet commenced commercialization in their respective territories. Basis of Presentation — The accompanying condensed consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The Company is not currently profitable and has rarely generated positive net cash flow from operations. In addition, the Company expects to continue to incur significant expenditures for the foreseeable future in support of its manufacturing operations, sales and marketing costs for Afrezza, and development costs for product candidates in the Company’s pipeline. As of March 31, 2020, the Company had an accumulated deficit of $3.0 billion and $120.3 million of total principal amount of outstanding borrowings, with limited capital resources of $38.9 million in cash and cash equivalents. These financial conditions raise substantial doubt about the Company’s ability to continue as a going concern. In August 2019, the Company and its wholly owned subsidiary, MannKind LLC, entered into a credit and security agreement with MidCap Financial Trust (as amended, the “MidCap Credit Facility”) to restructure its existing debts and to provide additional operating capital (the “recapitalization”) (Refer to Note 6 – Borrowings Collaboration and Licensing Arrangements Principal payments on the MidCap Credit Facility begin in September 2021. In addition, the MidCap Credit Facility contains certain covenants, one of which includes a requirement to maintain a minimum of $15.0 million of unrestricted cash and cash equivalents at all times. This amount will increase to $20.0 million if the Company draws the aforementioned additional funding that may be made available. The Company’s capital resources may not be sufficient to continue to meet its current and anticipated obligations over the next twelve months if the Company cannot increase its operating cash inflows by growing revenue or obtaining access to the remaining $25.0 million in borrowings that may become available under its MidCap Credit Facility. In the event these capital resources are not sufficient, the Company may need to raise additional capital by selling equity or debt securities, entering into strategic business collaboration agreements with other companies, seeking other funding facilities, or licensing arrangements, selling assets or by other means. However, the Company cannot provide assurances that additional capital will be available on acceptable terms or at all. If the Company is unable to meet its current and anticipated obligations over the next twelve months through its existing capital resources, or obtain new sources of capital when needed, the Company may have to reduce the scope of its commercial operations, reduce or eliminate one or more of its development programs, or make significant changes to its operating plan. These factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments that might result from the outcome of this uncertainty. Principles of Consolidation — The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. Intercompany balances and transactions have been eliminated. Certain prior year amounts have been reclassified for consistency with the current year presentation. These reclassifications had no effect on the reported condensed consolidated balance sheets or statements of operations. An adjustment has been made to the condensed consolidated statements of stockholder’s deficit as of March 31, 2019 to combine the exercise of stock options and the issuance of common stock from the release of restricted stock units. An additional adjustment has been made to the condensed consolidated statements of cash flows for the three months ended March 31, 2019 to combine restricted stock unit award with other, net in the cash flows from operating activities. These changes in classification do not affect previously reported cash flows from investing or financing activities. Segment Information — Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. To date, the Company has viewed its operations and manages its business as one segment operating in the United States of America. Revenue Recognition — The Company adopted Accounting Standards Codification (“ASC”) Topic 606 - Revenue from Contracts with Customers (“the new revenue guidance”), on January 1, 2018. Under Topic 606, the Company recognizes revenue when its customers obtain control of promised goods or services, in an amount that reflects the consideration which the Company expects to be entitled in exchange for those goods or services. To determine revenue recognition for arrangements that are within the scope of Topic 606, the Company performs the following five steps: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to arrangements that meet the definition of a contract under Topic 606, including when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of Topic 606, the Company assesses the goods or services promised within each contract, determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company has two types of contracts with customers: (i) contracts for commercial product sales with wholesale distributors and specialty pharmacies and (ii) collaboration arrangements. Revenue Recognition – Net Revenue – Commercial Product Sales – The Company sells Afrezza to a limited number of wholesale distributors and specialty pharmacies in the U.S. (collectively, its “Customers”). Wholesale distributors subsequently resell the Company’s products to retail pharmacies and certain medical centers or hospitals. Specialty pharmacies sell directly to patients. In addition to distribution agreements with Customers, the Company enters into arrangements with payors that provide for government mandated and/or privately negotiated rebates, chargebacks, and discounts with respect to the purchase of the Company’s products. The Company recognizes revenue on product sales when the Customer obtains control of the Company's product, which occurs at delivery for wholesale distributors and generally for specialty pharmacies. Product revenues are recorded net of applicable reserves for variable consideration, including discounts and allowances. Free Goods Program – From time to time, the Company offers programs to potential new patients that allow them to obtain free goods (prescription fills) from a pharmacy. T he Company excludes such amounts from both gross and net revenue. The cost of product associated with the free goods program is included in cost of goods sold. Reserves for Variable Consideration — Revenues from product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established. Components of variable consideration include trade discounts and allowances, product returns, provider chargebacks and discounts, government rebates, payor rebates, and other incentives, such as voluntary patient assistance, and other allowances that are offered within contracts between the Company and its Customers, payors, and other indirect customers relating to the Company’s sale of its products. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and result in a reduction of accounts receivable or establishment of a current liability. Significant judgments are required in making these estimates. Where appropriate, these estimates take into consideration a range of possible outcomes which are probability-weighted in accordance with the expected value method in Topic 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reduce recognized revenue to the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts. The amount of variable consideration which is included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under the contract will not occur in a future period. The Company’s analysis also contemplates application of the constraint in accordance with the guidance, under which it determined a material reversal of revenue would not occur in a future period for the estimates detailed below as of March 31, 2020 and, therefore, the transaction price was not reduced further during the three months ended March 31, 2020. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net revenue — commercial product sales and earnings in the period such variances become known. Trade Discounts and Allowances — The Company generally provides Customers with discounts which include incentives, such as prompt pay discounts, that are explicitly stated in the Company’s contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, the Company compensates (through trade discounts and allowances) its Customers for sales order management, data, and distribution services. However, the Company has determined such services received to date are not distinct from the Company’s sale of products to the Customer and, therefore, these payments have been recorded as a reduction of revenue and as a reduction to accounts receivable, net. Product Returns — Consistent with industry practice, the Company generally offers Customers a right of return for unopened product that has been purchased from the Company for a period beginning six months prior to and ending 12 months after its expiration date , which lapses upon shipment to a patient. The Company estimates the amount of its product sales that may be returned by its Customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized, as well as reductions to accounts receivable, net. The Company currently estimates product returns using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. The Company’s current return reserve percentage is estimated to be in the single-digits. Adjustments to the returns reserve have been made in the past and may be necessary in the future based on revised estimates to our assumptions. Provider Chargebacks and Discounts — Chargebacks for fees and discounts to providers represent the estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at prices lower than the list prices charged to Customers who directly purchase the product from the Company. Customers charge the Company for the difference between what they pay for the product and the ultimate selling price to the qualified healthcare providers. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is recorded in accrued expenses and other current liabilities. Chargeback amounts are generally determined at the time of resale to the qualified healthcare provider by Customers, and the Company generally issues credits for such amounts within a few weeks of the Customer’s notification to the Company of the resale. Reserves for chargebacks consist of credits that the Company expects to issue for units that remain in the distribution channel inventories at each reporting period-end that the Company expects will be sold to qualified healthcare providers, and chargebacks that Customers have claimed, but for which the Company has not yet issued a credit. Government Rebates — The Company is subject to discount obligations under Medicare and state Medicaid programs. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities. Estimates around Medicaid have historically required significant judgement due to timing lags in receiving invoices for claims from states. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom the Company will owe an additional liability under the Medicare Part D program. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Payor Rebates — The Company contracts with certain private payor organizations, primarily insurance companies and pharmacy benefit managers, for the payment of rebates with respect to utilization of its products. The Company estimates these rebates, including estimates for product that has been recognized as revenue, but which remains in the distribution channel, and records such estimates in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities. Other Incentives — Other incentives which the Company offers include voluntary patient support programs, such as the Company's co-pay assistance program, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with the product that has been recognized as revenue, but remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities. Revenue Recognition — Revenue — Collaborations and Services — The Company enters into licensing or research agreements under which the Company licenses certain rights to its product candidates to third parties or conducting research services to third parties. The terms of these arrangements may include , but are not limited to payment to the Company of one or more of the following: up-front license fees; development, regulatory, and commercial milestone payments; payments for manufacturing commercial and clinical supply services the Company provides; and royalties on net sales of licensed products and sublicenses of the rights. As part of the accounting for these arrangements, the Company must develop assumptions that require judgment such as determining the performance obligation in the contract and determining the stand-alone selling price for each performance obligation identified in the contract. If an arrangement has multiple performance obligations, the allocation of the transaction price is determined from observable market inputs, and the Company uses key assumptions to determine the stand-alone selling price, which may include development timelines, reimbursement rates for personnel costs, discount rates, and probabilities of technical and regulatory success. Revenue is recognized based on the measurement of progress as the performance obligation is satisfied and consideration received that does not meet the requirements to satisfy the revenue recognition criteria is recorded as deferred revenue. Current deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months. Amounts that the Company expects will not be recognized within the next 12 months are classified as long-term deferred revenue. For further information see Note 7 – . The Company recognizes upfront license payments as revenue upon delivery of the license only if the license is determined to be a separate unit of accounting from the other undelivered performance obligations. The undelivered performance obligations typically include manufacturing or development services or research and/or steering committee services. If the license is not considered as a distinct performance obligation, then the license and other undelivered performance obligations would be evaluated to determine if such should be accounted for as a single unit of accounting. If concluded to be a single performance obligation, the transaction price for the single performance obligation is recognized as revenue over the estimated period of when the performance obligation is satisfied. Whenever the Company determines that an arrangement should be accounted for over time, the Company determines the period over which the performance obligations will be performed, and revenue will be recognized over the period the Company is expected to complete its performance obligations. Significant management judgment is required in determining the level of effort required under an arrangement and the period over which the Company is expected to complete its performance obligations under an arrangement. The Company’s collaboration agreements typically entitle the Company to additional payments upon the achievement of development, regulatory and sales milestones. If the achievement of a milestone is considered probable at the inception of the collaboration, the related milestone payment is included with other collaboration consideration, such as upfront fees and research funding, in the Company’s revenue calculation. If these milestones are not considered probable at the inception of the collaboration, the milestones will typically be recognized in one of two ways depending on the timing of when the milestone is achieved. If the milestone is improbable at inception and subsequently deemed probable of achievement, such will be added to the transaction price, resulting in a cumulative adjustment to revenue. If the milestone is achieved after the performance period has completed and all performance obligations have been delivered, the Company will recognize the milestone payment as revenue in its entirety in the period the milestone was achieved. The Company’s collaborative agreements, for accounting purposes, represent contracts with customers and therefore are not subject to accounting literature on collaborative agreements. The Company grants licenses to its intellectual property, supplies raw materials or finished goods and provides research and development services, all of which are outputs of the Company’s ongoing activities, in exchange for consideration. The Company does not develop assets jointly with collaboration partners, and does not share in significant risks of their development or commercialization activities. Accordingly, the Company concluded that its collaborative agreements must be accounted for pursuant to Topic 606, Revenue from Contracts with Customers. For collaboration agreements that allow collaboration partners to select additional optioned products or services, the Company evaluates whether such options contain material rights (i.e., have exercise prices that are discounted compared to what the Company would charge for a similar product or service to a new collaboration partner). The exercise price of these options includes a combination of licensing fees, event-based milestone payments and royalties. When these amounts in aggregate are not offered at a discount that exceeds discounts available to other customers, the Company concludes the option does not contain a material right, and therefore is not included in the transaction price at contract inception. Rather, the Company evaluates grants of additional licensing rights upon option exercises to determine whether such should be accounted for as separate contracts. The Company concluded there is no material right in these options. The Company follows detailed accounting guidance in measuring revenue and certain judgments affect the application of its revenue policy. For example, in connection with its existing collaboration agreements, the Company has recorded on its condensed consolidated balance sheets short-term and long-term deferred revenue based on its best estimate of when such revenue will be recognized. Short-term deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months. Amounts that the Company expects will not be recognized within the next 12 months are classified as long-term deferred revenue. However, this estimate is based on the Company’s current project development plan and, if the development plan should change in the future, the Company may recognize a different amount of deferred revenue over the next 12-month period. Milestone Payments — At the inception of each arrangement that includes development milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the customer, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as, or when, the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company will re-evaluate the probability of achievement of such development milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration, other revenue, and earnings in the period of adjustment. Cost of Goods Sold — Cost of goods sold includes material, labor costs and manufacturing overhead. Cost of goods sold also includes a significant component of current period manufacturing costs in excess of costs capitalized into inventory (excess capacity costs). These costs, in addition to the impact of the annual revaluation of inventory to standard costs, and write-offs of inventory are recorded as expenses in the period in which they are incurred, rather than as a portion of inventory costs. The cost of goods sold excludes the cost of insulin purchased under our Insulin Supply Agreement (see Note 10 – ). All insulin inventory on hand was written off and the full purchase commitment contract to purchase future insulin was accrued as a recognized loss on purchase commitments as of the end of 2015. Cash and Cash Equivalents and Restricted Cash —The Company considers all highly liquid investments with original or remaining maturities of 90 days or less at the time of purchase, that are readily convertible into cash to be cash equivalents. As of March 31, 2020 and December 31, 2019, cash equivalents were comprised of money market accounts with maturities less than 90 days from the date of purchase. The Company records restricted cash when cash and cash equivalents are restricted as to withdrawal or usage. The Company presents amounts of restricted cash that will be available for use within 12 months of the reporting date as restricted cash in current assets. Restricted cash amounts that will not be available for use in the Company’s operations within 12 months of the reporting date are presented as restricted cash in long term assets. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported on the consolidated balance sheets that sum to amounts reported on the consolidated statement of cash flows (in thousands): March 31, 2020 December 31, 2019 Cash and cash equivalents $ 38,868 $ 29,906 Restricted cash 316 316 Total cash, cash equivalents, and restricted cash $ 39,184 $ 30,222 Short-term Investments —The Company’s short-term investments consist of U.S. Treasury securities stated at amortized cost which the Company intends to hold until maturity. Those with maturities less than 12 months are included in short-term investments and any investments with maturities in excess of twelve months are included in long-term investments in our condensed consolidated balance sheets. As of March 31, 2020, the Company did not hold any short-term investments nor did it record any material gains or losses on short-term investment securities during the three months ended March 31, 2020. Concentration of Credit Risk — Financial instruments that potentially subject the Company to concentration of credit risk consist of cash and cash equivalents and short-term investments. Cash and cash equivalents are held in high credit quality institutions. Cash equivalents consist of interest-bearing money market accounts and U.S. Treasury securities, which are regularly monitored by management. Accounts Receivable and Allowance for Doubtful Accounts — Accounts receivable are recorded at the invoiced amount and are not interest bearing. Accounts receivable are presented net of an allowance for doubtful accounts if there are estimated losses resulting from the inability of its customers to make required payments. The Company makes ongoing assumptions relating to the collectability of its accounts receivable in its calculation of the allowance for doubtful accounts. Accounts receivable are also presented net of an allowance for product returns and trade discounts and allowances because the Company’s customers have the right of setoff for these amounts against the related accounts receivable. Pre-Launch Inventory — An improvement to the manufacturing process for the Company’s primary excipient FDKP was demonstrated to be viable and management expects to realize an economic benefit in the future as a result of such process improvement. Accordingly, the Company is required to assess whether to capitalize inventory costs related to such excipient prior to regulatory approval of the new supplier and the improved manufacturing process. In doing so, management must consider a number of factors in order to determine the amount of inventory to be capitalized, including the historical experience of achieving regulatory approvals for the Company’s manufacturing process, feedback from regulatory agencies on the changes being effected and the amount of inventory that is likely to be used in commercial production. The shelf life of the excipient will be determined as part of the regulatory approval process; in the interim, the Company must assess the available stability data to determine whether there is likely to be adequate shelf life to support anticipated future sales occurring beyond the expected approval date of the new raw material. If management is aware of any specific material risks or contingencies other than the normal regulatory review and approval process, or if the criteria for capitalizing inventory produced prior to regulatory approval are otherwise not met, the Company would not capitalize such inventory costs, choosing instead to recognize such costs as a research and development expense in the period incurred. Inventories — Inventories are stated at the lower of cost or net realizable value. The Company determines the cost of inventory using the first-in, first-out, or FIFO, method. The Company capitalizes inve

Accounts Receivable

Accounts Receivable	3 Months Ended
	Mar. 31, 2020
Receivables [Abstract]
Accounts Receivable	2. Accounts Receivable Accounts receivable, net consists of the following (in thousands): March 31, 2020 December 31, 2019 Accounts receivable, gross $ 8,393 $ 6,925 Wholesaler distribution fees and prompt pay discounts (1,458 ) (1,767 ) Reserve for returns (1,903 ) (1,645 ) Accounts receivable, net $ 5,032 $ 3,513 As of March 31, 2020 and December 31, 2019, the allowance for doubtful accounts was de minimis

Inventories

Inventories	3 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
Inventories	3. Inventories Inventories consist of the following (in thousands): March 31, 2020 December 31, 2019 Raw materials $ 1,643 $ 1,751 Work-in-process 495 1,432 Finished goods 1,093 972 Total inventory $ 3,231 $ 4,155 Work-in-process and finished goods as of March 31, 2020 and December 31, 2019 include conversion costs and exclude the cost of insulin. All insulin inventory on hand was written off and the projected loss on the purchase commitment contract to purchase future insulin was accrued as of the end of 2015. Raw materials inventory included $0.8 million of pre-launch inventory as of March 31, 2020 and December 31, 2019, which consisted of FDKP received in November 2019 that will be used to manufacture Afrezza under an enhanced manufacturing process for FDKP. The Company expects to receive FDA approval of the new source of FDKP in mid-2021, after which the pre-launch raw materials inventory will be reclassified as raw materials inventory for use in the manufacturing of Afrezza. The Company analyzed its inventory levels to identify inventory that may expire or has a cost basis in excess of its estimated realizable value. The Company also performed an assessment of projected sales and evaluated the lower of cost or net realizable value and the potential excess inventory on hand. Inventory that was forecasted to become obsolete due to expiration is recorded in costs of goods sold in the accompanying condensed consolidated statements of operations. For the three months ended March 31, 2020 there was an inventory write-off of $0.5 million as a result of this assessment. There was no inventory write-off for the three months ended March 31, 2019.

Property and Equipment

Property and Equipment	3 Months Ended
	Mar. 31, 2020
Property Plant And Equipment [Abstract]
Property and Equipment	4. Property and Equipment Property and equipment consists of the following (in thousands): Estimated Useful Life (Years) March 31, 2020 December 31, 2019 Land — $ 875 $ 875 Buildings 39-40 17,389 17,389 Building improvements 5-40 37,543 37,543 Machinery and equipment 3-15 54,978 54,982 Furniture, fixtures and office equipment 5-10 3,005 3,005 Computer equipment and software 3 8,319 8,234 Construction in progress — 176 114 122,285 122,142 Less accumulated depreciation (95,768 ) (95,364 ) Total property and equipment, net $ 26,517 $ 26,778 Depreciation expense related to property and equipment was as follows (in thousands): Three Months Ended March 31, 2020 2019 Depreciation Expense $ 443 $ 367

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	3 Months Ended
	Mar. 31, 2020
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	5. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities were comprised of the following (in thousands): March 31, 2020 December 31, 2019 Salary and related expenses $ 10,217 $ 8,835 Discounts and allowances for commercial product sales 3,534 3,162 Deferred lease liability 1,415 1,433 Milestone Rights liability — current 1,337 — Professional fees 314 620 Sales and marketing services 309 147 Accrued interest 337 409 Other 863 1,298 Total accrued expenses and other current liabilities $ 18,326 $ 15,904

Borrowings

Borrowings	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Borrowings	6. Borrowings Carrying amount of borrowings consist of the following (in thousands): March 31, 2020 December 31, 2019 Mann Group promissory notes $ 70,022 $ 70,020 Midcap Credit Facility 38,893 38,851 Senior notes (2020 notes and 2024 convertible notes) 10,101 10,028 Total debt — net carrying amount $ 119,016 $ 118,899 The following table provides a summary of the Company’s debt and key terms: Amount Due Terms March 31, 2020 December 31, 2019 Annual Interest Rate Maturity Date Conversion Price Mann Group convertible note $35.0 million (plus $1.6 million accrued interest paid-in-kind) $35.0 million (plus $1.0 million accrued interest paid-in-kind) 7.00% November 2024 $2.50 per share Mann Group non- convertible note $35.1 million (plus $1.6 million accrued interest paid-in-kind) $35.1 million (plus $1.0 million accrued interest paid-in-kind) 7.00% November 2024 N/A MidCap Credit Facility $40.0 million $40.0 million one-month LIBOR (2% floor) plus 6.75% August 2024 N/A 2024 convertible notes $5.0 million $5.0 million 5.75% November 2024 $3.00 per share June 2020 note $2.6 million $2.6 million — June 2020 N/A December 2020 note $2.6 million $2.6 million — December 2020 N/A The maturities of our borrowings as of March 31, 2020 are as follows (in thousands): Amounts 2020 $ 5,262 2021 4,444 2022 13,333 2023 13,333 2024 83,940 Thereafter — Total principal payments 120,312 Unamortized discount (450 ) Debt issuance costs (846 ) Total debt — net carrying amount $ 119,016 MidCap Credit Facility — In August 2019, the Company closed the MidCap Credit Facility, which provides a secured term loan facility with an aggregate principal amount of up to $75.0 million. The Company borrowed the first advance of $40.0 million (“Tranche 1”) on August 6, 2019. Under the terms of the MidCap Credit Facility, the second advance of $10.0 million (“Tranche 2”) was available to the Company until April 15, 2020, provided that the Company had achieved Afrezza net revenue of at least $30.0 million on a trailing twelve month basis by that date (which was not achieved). The third advance of $25.0 million (“Tranche 3”) will be available to the Company until June 30, 2021, subject to the satisfaction of certain milestone conditions associated with Afrezza trailing net revenue and certain milestone conditions related to the Company’s collaboration with United Therapeutics (see Note 7 – ). As of March 31, 2020, the Company has recognized a $1.5 million impairment of the commitment asset, as it is unlikely that the milestone conditions related to Afrezza trailing net revenue will be achieved. In addition, the COVID-19 pandemic is expected to negatively impact the milestone conditions related to the Company’s collaboration with United Therapeutics. U namortized debt issuance costs was $0.8 million and unamortized debt discount was $0.3 million as of March 31, 2020. In December 2019, the Company entered into an amendment to the MidCap Credit Facility, pursuant to which the parties agreed to (i) amend the financial covenant relating to trailing twelve month minimum Afrezza Net Revenue (as defined in the MidCap Credit Facility) requirements, (ii) add a condition to the third advance of $25.0 million that requires the Company achieve certain amounts of Afrezza Net Revenue, and (iii) increase the exit fee from 6.00% to 7.00% of the principal amount of all term loans advanced to the Company under the MidCap Credit Facility. Tranche 1 and, if borrowed, Tranche 3, each accrue interest at an annual rate equal to one-month LIBOR plus 6.75%, subject to a one-month LIBOR floor of 2.00%. Interest on each term loan advance is due and payable monthly in arrears. Principal on the term loan advance under Tranche 1 is payable in 36 equal monthly installments beginning September 1, 2021, until paid in full on August 1, 2024, and principal on any term loan advance under Tranche 3 is payable beginning on the later of (i) September 1, 2021, and (ii) the first day of the first full calendar month immediately following such term loan advance, in an amount equal to the outstanding term loan advance in respect of Tranche 3 divided by the number of full calendar months remaining before August 1, 2024. The Company has the option to prepay the term loans, in whole or in part, subject to early termination fees in an amount equal to 3.00% of principal prepaid if prepayment occurs on or prior to the first anniversary of the closing date, 2.00% of principal prepaid if prepayment occurs after the first anniversary of the closing date but on or prior to the second anniversary of the closing date, and 1.00% of principal prepaid if prepayment occurs after the second anniversary of the closing date and prior to or on the third anniversary of the closing date. In connection with execution of the MidCap Credit Facility, the Company paid MidCap a $0.4 million origination fee. The Company’s obligations under the MidCap Credit Facility are secured by a security interest on substantially all of its assets, including intellectual property. The MidCap Credit Facility contains customary affirmative covenants and customary negative covenants limiting the Company’s ability and the ability of the Company’s subsidiaries to, among other things, dispose of assets, undergo a change in control, merge or consolidate, make acquisitions, incur debt, incur liens, pay dividends, repurchase stock and make investments, in each case subject to certain exceptions. The Company must also comply with a financial covenant relating to trailing twelve month minimum Afrezza net revenue, tested on a monthly basis, and a minimum cash covenant of $15.0 million at all times, which will increase to $20.0 million following the funding of Tranche 3. As of March 31, 2020, the Company was in compliance with the financial and minimum cash covenants. The MidCap Credit Facility also contains customary events of default relating to, among other things, payment defaults, breaches of covenants, a material adverse change, listing of the Company’s common stock, bankruptcy and insolvency, cross defaults with certain material indebtedness and certain material contracts, judgments, and inaccuracies of representations and warranties. Upon an event of default, the agent and the lenders may declare all or a portion of the Company’s outstanding obligations to be immediately due and payable and exercise other rights and remedies provided for under the MidCap Credit Facility. During the existence of an event of default, interest on the term loans could be increased by 2.00%. The Company also agreed to issue warrants to purchase shares of the Company’s common stock (the “MidCap warrants”) upon the drawdown of each term loan advance under the MidCap Credit Facility in an aggregate amount equal to 3.25% of the amount drawn, divided by the exercise price per share for that tranche. The exercise price per share is equal to the volume-weighted average closing price of the Company’s common stock for the ten business days immediately preceding the second business day before the issue date. As a result of Tranche 1, the Company issued warrants to purchase an aggregate of 1,171,614 shares of the Company’s common stock, at an exercise price equal to $1.11 per share. The MidCap warrants are immediately exercisable and expire on the earlier to occur of the seventh anniversary of the respective issue date or, in certain circumstances, the closing of a merger, sale or other consolidation transactions in which the consideration is cash, stock of a publicly traded acquirer, or a combination thereof. The Company determined that these warrants met the criteria for equity classification and accounted for such warrants in additional paid-in capital. Senior Notes — As of March 31, 2020 and December 31, 2019, there was $10.2 million principal amount of senior notes outstanding, respectively. In August 2019, the Company entered into a privately-negotiated exchange agreement with the holder of , among other things, (i) repaid $1.5 million in cash to such holder, (ii) issued 4,017,857 shares of the Company’s common stock to such holder (at a conversion price of $1.12 per share), (iii) issued to such holder in the principal amount of $5.0 million and (iv) issued a , all in exchange for the cancellation of the $18.7 million in principal amount of the 2021 notes. The 2020 notes may be prepaid at any time on or prior to their respective maturity dates of June 30, 2020 and December 31, 2020 at the option of the Company. In addition, the Company may elect to pay the 2020 notes at any time on or prior to their respective maturity dates, if certain conditions are met, in shares of the Company’s common stock at a price per share equal to the last reported sale price on the trading day immediately prior to the payment date The 2024 convertible notes were issued pursuant to an indenture, dated as of August 6, 2019, between the Company and U.S. Bank National Association, as trustee (the “Indenture”). The 2024 convertible notes are the Company’s general, unsecured obligations, and are subordinated in right of payment to the indebtedness incurred pursuant to the MidCap Credit Facility. The 2024 convertible notes rank equally in right of payment with the Company’s other unsecured senior debt. The 2024 convertible notes accrue interest at the rate of 5.75% per year on the principal amount, payable semiannually in arrears on February 15 and August 15 of each year, beginning February 15, 2020, with interest accruing from August 6, 2019. Interest on the 2024 convertible notes will be payable in cash or, at the option of the Company if certain conditions are met, in shares of the Company’s common stock at a price per share equal to the last reported sale price on the trading day immediately prior to the interest payment date. The 2024 convertible notes will mature on the earlier of (i) November 4, 2024 or (ii) the 91 st The 2024 convertible notes are convertible, at the option of the holder, at any time on or prior to the close of business on the business day immediately preceding the stated maturity date, into shares of the Company’s common stock at a conversion rate of 333.3333 shares per $1,000 principal amount of 2024 convertible notes, which is equal to a conversion price of approximately $3.00 per share. If certain bankruptcy and insolvency-related events of default occur, the principal of, and accrued and unpaid interest on, all of the then outstanding 2024 convertible notes shall automatically become due and payable. If an event of default other than certain bankruptcy and insolvency-related events of defaults occurs and is continuing, the Trustee or the holders of at least 25% in aggregate principal amount of the then-outstanding 2024 convertible notes, by written notice to the Trustee, may declare the 2024 convertible notes due and payable at their principal amount plus any accrued and unpaid interest, and thereupon the Trustee may, at its discretion, proceed to protect and enforce the rights of the holders by the appropriate judicial proceedings. Notwithstanding the foregoing, the Indenture provides that, to the extent the Company elects, the sole remedy for an event of default relating to certain failures by the Company to comply with certain reporting covenants in the Indenture will, for the first 180 days after such event of default, consist exclusively of the right to receive additional interest on the 2024 convertible notes. If the Company undergoes certain fundamental changes, except in certain circumstances, each holder of convertible notes will have the option to require the Company to repurchase all or any portion of that holder’s convertible notes. The fundamental change repurchase price will be 100% of the principal amount of the convertible notes to be repurchased plus accrued and unpaid interest, if any. The Company may elect at its option to cause all or any portion of the 2024 in equals or Mann Group promissory notes — In August 2019, the Company entered into a privately-negotiated exchange agreement with The Mann Group LLC (the “Mann Group”), pursuant to which, among other things, the Company (i) repaid $3.0 million in cash to the Mann Group, (ii) issued 7,142,857 shares of the Company’s common stock to the Mann Group (at a conversion price of $1.12 per share), (iii) issued a $35.0 million note that is convertible into shares of the Company’s common stock at $2.50 per share (the “Mann Group convertible note”) and (iv) issued a non-convertible note to the Mann Group in an aggregate principal amount of $35.1 million (the “Mann Group non-convertible note” and , together with the Mann Group convertible note, the “Mann Group promissory notes”) , all in exchange for the cancellation of the $71.5 million in principal and approximately $9.5 million in accrued interest paid-in-kind under the existing Mann Group loan arrangement. The Mann Group promissory notes each accrue interest at the rate of 7.00% per year on the principal amount, payable quarterly in arrears on the first day of each calendar quarter beginning October 1, 2019. The Mann Group convertible note will mature on November 3, 2024. The principal and any accrued and unpaid interest under the Mann Group convertible note may be converted, at the option of the Mann Group, at any time on or prior to the close of business on the business day immediately preceding the stated maturity date, into shares of the Company’s common stock at a conversion rate of 400 shares per $1,000 of principal and/or accrued and unpaid interest, which is equal to a conversion price of $2.50 per share. The conversion rate will be subject to adjustment under certain circumstances described in the Mann Group convertible note. Interest on the Mann Group convertible note will be payable in kind by adding the amount thereof to the principal amount; provided that with respect to interest accruing from and after January 1, 2021, the Company may, at its option, elect to pay any such interest on any interest payment date, if certain conditions are met, in shares of the Company’s common stock at a price per shall equal to the last reported sale price on the trading day immediately prior to the payment date. The Mann Group non-convertible note will mature on the earlier of (i) November 3, 2024 or (ii) the 90th day after the repayment in full, and termination and discharge of all obligations (other than contingent indemnity obligations) under the MidCap Credit Facility. Interest on the Mann Group non-convertible note will be payable in kind by adding the amount thereof to the principal amount; provided that MannKind may, at its option, elect to pay any such interest on any interest payment date, if certain conditions are met, in shares of MannKind’s common stock at a price per shall equal to the last reported sale price on the trading day immediately prior to the interest payment date. Amortization of the premium and accretion of debt issuance costs related to all borrowings for the three months ended March 31, 2020 and 2019 are as follows (in thousands): Three Months Ended March 31, 2020 2019 Amortization of debt discount $ 89 $ 72 Accretion expense — debt issuance cost (27 ) (22 ) Amortization of debt premium — (95 ) Milestone Rights — As of March 31, 2020 and December 31, 2019, the remaining Milestone Rights liability balance was $7.3 million, which was based on initial fair value estimates calculated using the income approach and reduced by milestone achievement payments made. During the third quarter of 2019, the Company achieved the first Afrezza net sales milestone specified by the Milestone Rights. The Company currently estimates that it will reach the next milestone in the fourth quarter of 2020, at which point the Company will be required to make a $5.0 million payment in the following quarter. The carrying value of the Milestone Rights liability related to this $5.0 million payment is approximately $1.3 million, which represents the fair value related to this payment that was determined in 2013 (the most recent measurement date). Accordingly, approximately $1.3 million in value related to the next milestone payment was recorded in accrued expenses and other current liabilities and the remaining long-term portion of $5.9 million is included as Milestone Rights liability in the accompanying condensed consolidated balance sheets as of March 31, 2020. The Milestone Right liability as of December 31, 2019 was $7.3 million. The agreement with the Milestone Purchasers that provides for the Milestone Rights includes customary representations and warranties and covenants by the Company, including restrictions on transfers of intellectual property related to Afrezza. The Milestone Rights are subject to acceleration in the event the Company transfers its intellectual property related to Afrezza in violation of the terms of such agreement. The Company has initially recorded the Milestone Rights at their estimated fair value.

Collaborations and Licensing Ar

Collaborations and Licensing Arrangements	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaborations and Licensing Arrangements	7. Collaboration and Licensing Arrangements Revenue from collaborations and services for the three months ended March 31, 2020 and 2019 are as follows (in thousands): Three Months Ended March 31, 2020 2019 UT License Agreement $ 7,978 $ 7,615 UT Research Agreement 158 4,658 Receptor CLA 62 62 Cipla distribution agreement 37 37 Total revenue from collaborations and services $ 8,235 $ 12,372 United Therapeutics License Agreement — In September 2018, the Company and United Therapeutics Corporation (“United Therapeutics” or “UT”) entered into an exclusive global license and collaboration agreement (the “UT License Agreement”) for the rights to the Company’s dry powder formulation of treprostinil (“TreT”) and associated inhalation delivery devices. Under the UT License Agreement, UT is responsible for global development, regulatory and commercial activities with respect to TreT. The Company is responsible for manufacturing clinical supplies and commercial supplies of TreT. Under the terms of the UT License Agreement, the Company received an upfront payment of $45.0 million in October 2018 and two $12.5 million milestone payments in 2019. The Company may receive additional milestone payments of up to $25.0 million upon the achievement of specified development targets. The Company will also be entitled to receive low double-digit royalties on net sales of TreT. UT, at its option, may expand the scope of the products covered by the UT License Agreement to include products with certain other active ingredients for the treatment of pulmonary arterial hypertension. Each such optioned product would be subject to UT’s payment to the Company of up to $40.0 million in additional option exercise and development milestone payments, as well as a low double-digit royalty on net sales of any such product. The Company recognizes revenue on a ratable basis from October 2018 through December 2021; the estimated date when its performance obligations for development activities under UT License Agreement will be substantially completed. At the inception of the agreement, the Company identified one distinct, performance obligation. The Company determined that the key deliverables include the license, supply of product to be used in clinical development, and certain research services upon achievement of specified development targets. Due to the specialized and unique nature of these services and their direct relationship with the license, the Company has determined that these deliverables represent one distinct bundle and thus, one performance obligation. The Company also determined that UT’s option to expand the scope of the products to include products with other active ingredients is not a material right, and thus, not a performance obligation at the onset of the agreement. The consideration for the option will be accounted for upon exercise of the option. The Company expects to complete the activities specified in the development plan and to achieve the remaining milestone events for total consideration of approximately $101.4 million, which includes an upfront payment, four milestone payments and various pass-through costs. Future commercial supply remains at UT’s option and is valued at a stand-alone selling price and, therefore, is not accounted for under the current arrangement. The Company believes that this method best reflects the measure of progress toward complete satisfaction of the performance obligation. Deferred revenue related to the UT License Agreement is being recognized in net revenue — collaborations over a 13-quarter period ending December 31, 2021, which represents the estimated period to satisfy the performance obligation. As of March 31, 2020, the deferred revenue for the UT License Agreement consisted of $30.4 million, which was classified as a current liability. Deferred revenue is classified as part of current or long-term liability in the accompanying condensed consolidated balance sheets based on the Company’s estimate of the portion of the performance obligation that will be completed within the next 12 months, and includes payments received as well as payments receivable. United Therapeutics Research Agreement — In September 2018, the Company and UT also entered into a research agreement (“UT Research Agreement”) for the conduct of research and consulting services in connection with multiple potential products, including evaluating the feasibility of preparing a dry powder formulation of a compound for the treatment of pulmonary hypertension outside the scope of the UT License Agreement. In addition, UT, at its option, may obtain a license to develop, manufacture and commercialize products based on specified compounds within the drug classes covered by the UT Research Agreement. Each specified compound advanced into development and commercialization under such a license would be subject to the payment to the Company of additional milestone payments of up to $30.0 million and a low double-digit royalty on net sales of such products. In connection with the UT Research Agreement, the Company received an upfront payment of $10.0 million in September 2018. At the inception of the UT Research Agreement, the Company identified two distinct performance obligations. The Company determined that the key deliverables of each performance obligation include (i) the development of a product prototype (including a technical feasibility report) and; (ii) engineering consulting services. Due to the separately identifiable nature of these obligations, the Company has determined that these deliverables represent two distinct performance obligations. The Company also determined that UT’s option to expand the scope to include specific drug classes covered by the agreement is not a material right, and thus, not a performance obligation at the onset of the agreement. The consideration for the option will be accounted for upon exercise of the option. The Company allocated the total $10.0 million transaction price to its two distinct performance obligations based on available observable market inputs. A transaction price of $9.0 million was allocated to the product prototype and a transaction price of $1.0 million was allocated to engineering consulting services. The revenue for the product prototype is recognized using an output method (based on project milestones achieved and surveys of performance completed to date). The Company believes that this method best reflects the measure of progress toward complete satisfaction of the performance obligation. The revenue for the engineering consulting services was recognized using a ratable method until the obligation was satisfied. The Company believes that this method best reflects the measure of progress toward complete satisfaction of the performance obligation. As of March 31, 2020 the deferred revenue balance was $0.1 million, which was classified as a current liability in the accompanying condensed consolidated balance sheets. Receptor Collaboration and License Agreement — In 2016, the Company entered into a collaboration and license agreement (the “CLA”) with Receptor Life Sciences, Inc. (“Receptor”) pursuant to which Receptor subsequently acquired an exclusive license to develop, manufacture and commercialize products that use the Company’s technology to deliver certain compounds via oral inhalation in exchange for upfront license fees, milestone payments upon the completion of certain technology transfer activities and the achievement of specified sales targets as well as royalties upon Receptor’s and its sublicensees’ sale of products. A $1.0 million license fee received in 2016 was recorded in deferred revenue from collaborations as of December 31, 2016 and is being recognized in net revenue — collaborations over four years, the estimated period over which the Company is required to satisfy the remaining performance obligations. The remaining performance obligations are to provide certain technology transfer activities. As of March 31, 2020, the deferred revenue balance was $0.2 million, which was classified as a current liability in the accompanying condensed consolidated balance sheets. The additional payments referred to above represent variable consideration for which the Company has not recognized any revenue because it is uncertain that Receptor will be able to successfully develop, manufacture or sell product related to this license. There was no change to the accounting for this contract as a result of the initial application of the new revenue guidance since (i) the receipt of such payments is highly susceptible to factors outside of the Company’s influence, (ii) the uncertainty regarding the receipt of these payments is not expected to be resolved for years, and (iii) the Company has limited experience with similar contracts. See Note 1 – Description of Business and Significant Accounting Policies In 2017, the Company entered into a manufacturing and supply agreement with Receptor pursuant to which the Company agreed to provide certain raw materials and certain additional research and formulation consulting services to Receptor. For the three months ended March 31, 2020 and 2019, the additional research and formulation services provided to Receptor were de minimis Biomm Supply and Distribution Agreement — In May 2017, the Company and Biomm S.A. entered into a supply and distribution agreement for the commercialization of Afrezza in Brazil. Under this agreement, Biomm was responsible for pursuing regulatory approvals of Afrezza in Brazil, including from the Agência Nacional de Vigilância Sanitária (“ANVISA”) and, with respect to pricing matters, from the Camara de Regulação de Mercado de Medicamentos (“CMED”), both of which have now been received. The Company sold $0.7 million of product to Biomm in the third quarter of 2019 to launch Afrezza in Brazil, which was recognized as net revenue — commercial product sales in the respective period. Biomm commenced product sales in January 2020. Cipla License and Distribution Agreement — In May 2018, the Company and Cipla Ltd. (“Cipla”) entered into an exclusive agreement for the marketing and distribution of Afrezza in India and the Company received a $2.2 million nonrefundable license fee. Under the terms of the agreement, Cipla will be responsible for obtaining regulatory approvals to distribute Afrezza in India and for all marketing and sales activities of Afrezza in India. The Company is responsible for supplying Afrezza to Cipla. The Company has the potential to receive certain additional regulatory milestone payments, minimum purchase commitment revenue and royalties on Afrezza sales in India once cumulative gross sales have reached a specified threshold. The nonrefundable licensing fee was recorded in deferred revenue and is being recognized in net revenue – collaborations over 15 years, representing the estimated period to satisfy the performance obligation. The additional milestone payments represent variable consideration for which the Company has not recognized any revenue because of the uncertainty of obtaining marketing approval. The Company also recognized $0.2 million as income tax expense for a payment made to the India tax authority in 2018. As of March 31, 2020, the deferred revenue balance was $1.9 million, of which $0.1 million is classified as current and $1.8 million is classified as long term in the accompanying condensed consolidated balance sheets. AMSL Distribution Agreement — In May 2019, the Company entered into an exclusive marketing and distribution agreement with the AMSL Diabetes division of Australasian Medical & Scientific Ltd. (“AMSL Diabetes”) for the commercialization of Afrezza in Australia. Under the terms of this agreement, AMSL Diabetes is responsible for obtaining regulatory and reimbursement approvals to distribute Afrezza in Australia. Upon regulatory approval, AMSL Diabetes will conduct sales, marketing, and customer support and distribution activities whereas the Company will be responsible for the supply and manufacturing of Afrezza.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	8. Fair Value of Financial Instruments The availability of observable inputs can vary among the various types of financial assets and liabilities. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for financial statement disclosure purposes, the level in the fair value hierarchy within which the fair value measurement is categorized is based on the lowest level input that is significant to the overall fair value measurement. The Company uses the exit price method for estimating the fair value of loans for disclosure purposes. The carrying amounts reported in the accompanying condensed consolidated financial statements for cash, accounts receivable, accounts payable, and accrued expenses and other current liabilities (excluding the Milestone Rights liability) approximate their fair value due to their relatively short maturities. The fair value of the cash equivalents, MidCap Credit Facility, Mann Group promissory notes, 2024 convertible notes, 2020 notes, and Milestone Rights liabilities are disclosed below. Cash Equivalents and Restricted Cash — Cash equivalents consist of highly liquid investments with original or remaining maturities of 90 days or less at the time of purchase that are readily convertible into cash. As of March 31, 2020 and December 31, 2019, the Company held $38.9 million and $29.9 million, respectively, of cash and cash equivalents. The Company held $0.3 million in restricted cash as of March 31, 2020 and December 31, 2019, which was comprised of money market funds. Restricted cash is used to collateralize a letter of credit. The fair value of these money market funds was determined by using quoted prices for identical investments in an active market (Level 1 in the fair value hierarchy). Short-term investments — Short-term investments consist of highly liquid investments that are intended to facilitate liquidity and capital preservation. The fair value of short-term investments approximate their carrying value. The measurement of which is based on a market approach using quoted market values (Level 1 in the fair value hierarchy). As of March 31, 2020, the Company did not hold any short-term investments. The fair value measurement of debt instruments is based on a discounted cash flow model and is sensitive to the change in yield (Level 3 in the fair value hierarchy): Hypothetical Change in Yield Hypothetical Change in Notes Payable Yield % Change Hypothetical Yield FV of Notes FV $ Change % Change (in millions) Mann Group promissory notes: (with conversion feature) 35.0 % 2 % 37.0 % $ 38.0 $ 36.4 $ (1.6 ) -4.2 % 35.0 % -2 % 33.0 % $ 38.0 $ 39.8 $ 1.8 4.7 % 35.0 % 4 % 39.0 % $ 38.0 $ 34.8 $ (3.2 ) -8.4 % 35.0 % -4 % 31.0 % $ 38.0 $ 41.8 $ 3.8 10.0 % Senior notes: (with conversion feature) 35.0 % 2 % 37.0 % $ 7.6 $ 7.5 $ (0.1 ) -1.3 % 35.0 % -2 % 33.0 % $ 7.6 $ 7.8 $ 0.2 2.6 % 35.0 % 4 % 39.0 % $ 7.6 $ 7.4 $ (0.2 ) -2.6 % 35.0 % -4 % 31.0 % $ 7.6 $ 7.9 $ 0.3 3.9 % MidCap Credit Facility 17.0 % 1 % 18.0 % $ 35.8 $ 35.1 $ (0.7 ) -2.0 % 17.0 % -1 % 16.0 % $ 35.8 $ 36.6 $ 0.8 2.2 % 17.0 % 2 % 19.0 % $ 35.8 $ 34.3 $ (1.5 ) -4.2 % 17.0 % -2 % 15.0 % $ 35.8 $ 37.4 $ 1.6 4.5 % Financial Liabilities — The following tables set forth the fair value of the Company’s financial instruments (in millions): March 31, 2020 Carrying Value Significant Unobservable Inputs (Level 3) Fair Value Financial liabilities: MidCap Credit Facility $ 38.9 $ 35.8 $ 35.8 2024 convertible notes 5.0 3.1 3.1 June 2020 note 2.6 2.4 2.4 December 2020 note 2.5 2.1 2.1 Mann Group promissory notes 70.0 38.0 38.0 Milestone rights 7.3 14.3 14.3 Total financial liabilities $ 126.3 $ 95.7 $ 95.7 December 31, 2019 Carrying Value Significant Unobservable Inputs (Level 3) Fair Value Financial liabilities: MidCap Credit Facility $ 38.9 $ 40.0 $ 40.0 2024 convertible notes 5.0 3.7 3.7 June 2020 note 2.5 2.3 2.3 December 2020 note 2.5 2.0 2.0 Mann Group promissory notes 70.0 46.2 46.2 Milestone rights 7.3 16.4 16.4 Total financial liabilities $ 126.2 $ 110.6 $ 110.6 Milestone Rights Liability — The fair value measurement of the Milestone Rights liability is sensitive to the discount rate and the timing of achievement of milestones. The Company utilized Monte-Carlo Simulation Method to simulate the Net Sales under a neutral framework to estimate the payment. The Company then discounted the future expected payments at cost of debt with a term equal to the simulated time to payout based on cumulative sales.

Stock-Based Compensation Expens

Stock-Based Compensation Expense	3 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation Expense	9. Stock-Based Compensation Expense Total stock-based compensation expense recognized in the accompanying condensed consolidated statements of operations for the three months ended March 31, 2020 and 2019 was as follows (in thousands): Three Months Ended March 31, 2020 2019 Restricted stock units and options $ 1,066 $ 883 Employee stock purchase plan 62 116 Total stock compensation expense $ 1,128 $ 999 During the three months ended March 31, 2020, the Company granted 230,000 The restricted stock units had a weighted average grant date fair value of $1.25 per share and a primary vesting period of four years. In addition, 42,067 restricted stock units were granted to non-employee directors with a weighted average grant date fair value of $1.17. The restricted stock units awarded to non-employee directors vested immediately upon grant, but the underlying shares of common stock will not be delivered to an individual director until there is a separation of service, such as resignation, retirement or death. During the three months ended March 31, 2020, the Company granted stock options to purchase an aggregate of 78,500 shares of common stock to certain employees at a weighted average exercise price of $1.25 per share. The options vest over a four year period. The weighted average grant date fair value was $0.93 per share, as determined using a Black-Scholes option pricing model, with the following key assumptions: risk-free interest rate of 0.79%; expected life of approximately 5.67 years ; volatility As of March 31, 2020, there was $8.0 million of unrecognized compensation expense related to options and performance options and $0.5 million of unrecognized compensation expense related to restricted stock units. For the options that are subject to performance conditions, the Company evaluates the probability that the performance conditions will be met and estimates the service period for recognition of the associated expense. During the three months ended March 31, 2019, the Company issued 754,729 restricted stock units to employees. During the three months ended March 31, 2019, the Company granted certain employees stock options to purchase an aggregate of

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies Guarantees and Indemnifications — In the ordinary course of its business, the Company makes certain indemnities, commitments and guarantees under which it may be required to make payments in relation to certain transactions. The Company, as permitted under Delaware law and in accordance with its Bylaws, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director is or was serving at the Company’s request in such capacity. The term of the indemnification period is for the officer’s or director’s lifetime. The maximum amount of potential future indemnification is unlimited; however, the Company has a director and officer insurance policy that may enable it to recover a portion of any future amounts paid. The Company believes the fair value of these indemnification agreements is minimal. The Company has not recorded any liability for these indemnities in the accompanying condensed consolidated balance sheets. However, the Company accrues for losses for any known contingent liability, including those that may arise from indemnification provisions, when future payment is probable and the amount can be reasonably estimated. No such losses have been recorded to date. Litigation — The Company is subject to legal proceedings and claims which arise in the ordinary course of its business. As of March 31, 2020, the Company believes that the final disposition of such matters will not have a material adverse effect on the financial position, results of operations or cash flows of the Company and no accrual has been recorded. The Company maintains liability insurance coverage to protect the Company’s assets from losses arising out of or involving activities associated with ongoing and normal business operations. The Company records a provision for a liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. The Company’s policy is to accrue for legal expenses in connection with legal proceedings and claims as they are incurred. Following the public announcement in January 2016 of the election by sanofi-aventis U.S. LLC (“Sanofi”) to terminate a license and collaboration agreement (the “Sanofi License Agreement”) between the Company and Sanofi and the subsequent decline in the Company’s stock price, two motions were submitted to the district court at Tel Aviv, Economic Department for the certification of a class action against the Company and certain of its officers and directors. In general, the complaints allege that the Company and certain of its officers and directors violated Israeli and U.S. securities laws by making materially false and misleading statements regarding the prospects for Afrezza, thereby artificially inflating the price of its common stock. The plaintiffs are seeking monetary damages. In November 2016, the district court dismissed one of the actions without prejudice. In the remaining action, the district court ruled in October 2017 that U.S. law will apply to this case. The plaintiff appealed this ruling, and following an oral hearing before the Supreme Court of Israel, decided to withdraw his appeal. Subsequently, in November 2018, the Company filed a motion to dismiss the certification motion. In September 2019, the plaintiff brought a motion to amend his claim, which the court denied in January 2020. The plaintiff has appealed this denial to the Supreme Court of Israel. The Company will continue to vigorously defend against the claims advanced. Contingencies — In July 2013, the Company also entered into an agreement with the Milestone Purchasers, pursuant to which the Company granted the Milestone Rights to receive payments up to $90.0 million upon the occurrence of specified strategic and sales milestones, $70.0 million of which remains payable upon achievement of such milestones (see Note 6 – ). Commitments — In July 2014, the Company entered into an Insulin Supply Agreement (the “Insulin Supply Agreement”) with Amphastar Pharmaceuticals, Inc. (“Amphastar”) pursuant to which Amphastar manufactures for and supplies to the Company certain quantities of recombinant human insulin for use in Afrezza. Under the terms of the Insulin Supply Agreement, Amphastar is responsible for manufacturing the insulin in accordance with the Company’s specifications and agreed-upon quality standards. In August 2019, the Company and Amphastar amended the Insulin Supply Agreement to extend the term to 2026 and to restructure the annual purchase commitments. As of March 31, 2020, the annual purchase requirements under the amended contract are as follows: Minimum Commitment 2020 € 6.6 million 2021 € 6.6 million 2022 € 8.5 million 2023 € 10.8 million 2024 € 14.6 million 2025 € 15.5 million 2026 € 19.4 million Unless terminated earlier, the term of the Insulin Supply Agreement expires on December 31, 2026 and can be renewed for additional, successive two year terms upon 12 months’ written notice given prior to the end of the initial term or any additional two year term. The Company and Amphastar each have normal and customary termination rights, including termination for a material breach that is not cured within a specific time frame or in the event of liquidation, bankruptcy or insolvency of the other party. In addition, the Company may terminate the Insulin Supply Agreement upon two years’ prior written notice to Amphastar without cause or upon 30 days’ prior written notice to Amphastar if a controlling regulatory authority withdraws approval for Afrezza, provided, however, in the event of a termination pursuant to either of the latter two scenarios, the provisions of the Insulin Supply Agreement require the Company to pay the full amount of all unpaid purchase commitments due over the initial term within 60 calendar days of the effective date of such termination. Warrants — In December 2018, the Company issued warrants to purchase up to an aggregate of 26,666,667 shares of the Company’s common stock (the “December warrants”) at an exercise price of $1.60 per share. As of March 31, 2020, 7,250,000 December warrants remain exercisable until June 26, 2020. In August 2019, in connection with the MidCap Credit Facility, the Company issued warrants to purchase an aggregate of 1,171,614 shares of the Company’s common stock, at an exercise price equal to $1.11 per share, to the lenders. Additional MidCap warrants will be issued if the Company accesses additional tranches under the MidCap Credit Facility (see Note 6 – Borrowings Vehicle Leases – During the second quarter of 2018, the Company entered into a lease agreement with Enterprise Fleet Management Inc. for the lease of 119 vehicles. The lease requires monthly payments of approximately $83,000 per month including the cost of maintaining the vehicles, taxes and insurance. The lease commenced when the Company took possession of the majority of the vehicles in the second quarter of 2018 and expires 48 months after the delivery date. During 2019, 29 vehicles were removed from the fleet, resulting in a fleet size of 90 vehicles. The revised monthly payment inclusive of maintenance fees, insurance and taxes is $65,000. The lease expense is included in selling, general and administrative expenses in the accompanying condensed consolidated statement of operations. Upon adoption of ASC 842, the agreement was classified as an operating lease which resulted in recording right-of-use assets and lease liabilities of approximately $1.6 million and $1.9 million, respectively, as of January 1, 2019. These amounts included approximately $1.6 million of non-current other assets and Office Lease — In May 2017, the Company executed an office lease with Russell Ranch Road II LLC for the Company’s corporate headquarters in Westlake Village, California. The office lease commenced in August 2017. The Company agreed to pay initial monthly lease payments of $40,951, subject to 3% annual increases, plus the estimated cost of maintaining the property and common areas by the landlord, with a five month concession from October 2017 through February 2018. The lease also provides for allowances for tenant alterations and maintenance. The lease expires in January 2023 and provides the Company with a five year renewal option. The lease expense is included in selling, general and administrative expenses in the accompanying condensed consolidated statement of operations. In November 2017, the Company executed an office lease with Russell Ranch Road II LLC to expand the office space for the Company’s corporate headquarters in Westlake Village, California. The office lease commenced in October 2018. The Company agreed to pay initial monthly lease payments of $35,969, subject to a 3% annual increase, plus the estimated operating cost of maintaining the property by the landlord, which are allocable based an annual assessment made by the landlord. In addition, the Company received reimbursement from the landlord of $56,325 for tenant improvements and was not required to pay a first-year common area maintenance fee. The lease expires in January 2023 and provides the Company with a five year renewal option. Upon adoption of ASC 842, this lease was classified as an operating lease which resulted in recording right-of-use assets and lease liabilities of approximately $3.2 million and $3.5 million, respectively, as of January 1, 2019. These amounts included approximately $0.9 million and $2.6 million of other current liabilities and operating lease liabilities, respectively. For the three months ended March 31, 2020, o perating lease costs under all operating leases, including office space and equipment, was approximately $0.4 million and cash paid was $0.4 million. Variable lease costs for the three months ended March 31, 2020 were approximately $0.1 million. The weighted average discount rate used was 7.5%. The weighted-average remaining lease term for all operating leases was 2.7 years. For the three months ended March 31, 2019, o perating lease costs under all operating leases, including office space and equipment, was approximately $0.5 million and cash paid was $0.5 million. Variable lease costs for the three months ended March 31, 2019 were approximately $0.1 million. The weighted average discount rate used was 7.2%. The weighted-average remaining lease term for all operating leases was 3.8 years. Future minimum office and vehicle lease payments as of March 31, 2020 and December 31, 2019, are as follows (in thousands): March 31, 2020 December 31, 2019 2020 $ 1,105 $ 1,470 2021 1,500 1,500 2022 1,241 1,241 2023 88 88 Total $ 3,934 $ 4,299

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes Management of the Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets and concluded, in accordance with the applicable accounting standards, that net deferred tax assets should be fully reserved. The Company has assessed its position with regards to uncertainty in tax positions and believes that its income tax filing positions and deductions will be sustained on audit and does not anticipate any adjustments that will result in a material change to its financial position. Therefore, no reserves for uncertain income tax positions have been recorded pursuant to this guidance. The Company’s tax years since 2015 remain subject to examination by federal, state and foreign tax authorities.

Subsequent Event

Subsequent Event	3 Months Ended
	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	12. Subsequent Events Paycheck Protection Program Loan – On April 10, 2020, the Company received the proceeds from a loan in the amount of approximately $4.9 million (the “PPP Loan”) from JPMorgan Chase Bank, N.A., as lender, pursuant to the Paycheck Protection Program (“PPP”) of the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”). The PPP Loan matures on April 9, 2022 and bears interest at a rate of 0.98% per annum. Commencing November 9, 2020, the Company is required to pay the lender equal monthly payments of principal and interest as required to fully amortize by April 9, 2022 the principal amount outstanding on the PPP Loan as of October 9, 2020. The PPP Loan is evidenced by a promissory note dated April 9, 2020, which contains customary events of default relating to, among other things, payment defaults and breaches of representations and warranties. The PPP Loan may be prepaid by the Company at any time prior to maturity with no prepayment penalties. All or a portion of the PPP Loan may be forgiven by the U.S. Small Business Administration (“SBA”) upon application by the Company beginning 60 days but not later than 120 days after loan approval and upon documentation of expenditures in accordance with the SBA requirements. Under the CARES Act, loan forgiveness is available for the sum of documented payroll costs, covered rent payments, covered interest and covered utilities during the eight week period beginning on the date of loan approval. For purposes of the CARES Act, payroll costs exclude compensation of an individual employee in excess of $100,000, prorated annually. Not more than 25% of the forgiven amount may be for non-payroll costs. Forgiveness is reduced if full-time headcount declines, or if salaries and wages for employees with salaries of $100,000 or less annually are reduced by more than 25%. In the event the PPP Loan, or any portion thereof, is forgiven pursuant to the PPP, the amount forgiven is applied to outstanding principal. The Company intends to use all proceeds from the PPP Loan to retain employees, maintain payroll and make lease, interest and utility payments.

Description of Business and S_2

Description of Business and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Financial Statement Estimates	Financial Statement Estimates — The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates or assumptions. Management considers many factors in selecting appropriate financial accounting policies, and in developing the estimates and assumptions that are used in the preparation of the financial statements. Management must apply significant judgment in this process and the threat of the COVID-19 pandemic has increased the level of judgment used by management in developing these estimates and assumptions. The COVID-19 pandemic continues to rapidly evolve and the ultimate impact of the COVID-19 pandemic is highly uncertain and subject to change. These effects could have a material impact on the estimates and assumptions used in the preparation of the accompanying condensed consolidated financial statements. The more significant estimates include revenue recognition and gross-to-net adjustments, assessing long-lived assets for impairment, clinical trial expenses, inventory costing and recoverability, recognized loss on purchase commitment, milestone rights liability, stock-based compensation and the determination of the provision for income taxes and corresponding deferred tax assets and liabilities, and the valuation allowance recorded against net deferred tax assets.
Business	Business — The Company is a biopharmaceutical company focused on the development and commercialization of inhaled therapeutic products for diabetes and orphan lung diseases, such as pulmonary arterial hypertension. The Company’s only approved product, Afrezza (insulin human) Inhalation Powder, is an ultra rapid-acting inhaled insulin that was approved by the U.S. Food and Drug Administration (the “FDA”) in June 2014 to improve glycemic control in adults with diabetes. Afrezza became available by prescription in United States retail pharmacies in February 2015. Currently, the Company promotes Afrezza to endocrinologists and certain high-prescribing primary care physicians in the United States through its specialty sales force. The Company’s partner in Brazil, Biomm S.A., commenced commercialization of Afrezza in January 2020. The Company’s partners in India and Australia are preparing for regulatory submissions and have not yet commenced commercialization in their respective territories.
Basis of Presentation	Basis of Presentation — The accompanying condensed consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The Company is not currently profitable and has rarely generated positive net cash flow from operations. In addition, the Company expects to continue to incur significant expenditures for the foreseeable future in support of its manufacturing operations, sales and marketing costs for Afrezza, and development costs for product candidates in the Company’s pipeline. As of March 31, 2020, the Company had an accumulated deficit of $3.0 billion and $120.3 million of total principal amount of outstanding borrowings, with limited capital resources of $38.9 million in cash and cash equivalents. These financial conditions raise substantial doubt about the Company’s ability to continue as a going concern. In August 2019, the Company and its wholly owned subsidiary, MannKind LLC, entered into a credit and security agreement with MidCap Financial Trust (as amended, the “MidCap Credit Facility”) to restructure its existing debts and to provide additional operating capital (the “recapitalization”) (Refer to Note 6 – Borrowings Collaboration and Licensing Arrangements Principal payments on the MidCap Credit Facility begin in September 2021. In addition, the MidCap Credit Facility contains certain covenants, one of which includes a requirement to maintain a minimum of $15.0 million of unrestricted cash and cash equivalents at all times. This amount will increase to $20.0 million if the Company draws the aforementioned additional funding that may be made available. The Company’s capital resources may not be sufficient to continue to meet its current and anticipated obligations over the next twelve months if the Company cannot increase its operating cash inflows by growing revenue or obtaining access to the remaining $25.0 million in borrowings that may become available under its MidCap Credit Facility. In the event these capital resources are not sufficient, the Company may need to raise additional capital by selling equity or debt securities, entering into strategic business collaboration agreements with other companies, seeking other funding facilities, or licensing arrangements, selling assets or by other means. However, the Company cannot provide assurances that additional capital will be available on acceptable terms or at all. If the Company is unable to meet its current and anticipated obligations over the next twelve months through its existing capital resources, or obtain new sources of capital when needed, the Company may have to reduce the scope of its commercial operations, reduce or eliminate one or more of its development programs, or make significant changes to its operating plan. These factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying financial statements do not include any adjustments that might result from the outcome of this uncertainty.
Principles of Consolidation	Principles of Consolidation — The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. Intercompany balances and transactions have been eliminated. Certain prior year amounts have been reclassified for consistency with the current year presentation. These reclassifications had no effect on the reported condensed consolidated balance sheets or statements of operations. An adjustment has been made to the condensed consolidated statements of stockholder’s deficit as of March 31, 2019 to combine the exercise of stock options and the issuance of common stock from the release of restricted stock units. An additional adjustment has been made to the condensed consolidated statements of cash flows for the three months ended March 31, 2019 to combine restricted stock unit award with other, net in the cash flows from operating activities. These changes in classification do not affect previously reported cash flows from investing or financing activities.
Segment Information	Segment Information — Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. To date, the Company has viewed its operations and manages its business as one segment operating in the United States of America.
Revenue Recognition	Revenue Recognition — The Company adopted Accounting Standards Codification (“ASC”) Topic 606 - Revenue from Contracts with Customers (“the new revenue guidance”), on January 1, 2018. Under Topic 606, the Company recognizes revenue when its customers obtain control of promised goods or services, in an amount that reflects the consideration which the Company expects to be entitled in exchange for those goods or services. To determine revenue recognition for arrangements that are within the scope of Topic 606, the Company performs the following five steps: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to arrangements that meet the definition of a contract under Topic 606, including when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of Topic 606, the Company assesses the goods or services promised within each contract, determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company has two types of contracts with customers: (i) contracts for commercial product sales with wholesale distributors and specialty pharmacies and (ii) collaboration arrangements.
Revenue Recognition - Net Revenue - Commercial Product Sales	Revenue Recognition – Net Revenue – Commercial Product Sales – The Company sells Afrezza to a limited number of wholesale distributors and specialty pharmacies in the U.S. (collectively, its “Customers”). Wholesale distributors subsequently resell the Company’s products to retail pharmacies and certain medical centers or hospitals. Specialty pharmacies sell directly to patients. In addition to distribution agreements with Customers, the Company enters into arrangements with payors that provide for government mandated and/or privately negotiated rebates, chargebacks, and discounts with respect to the purchase of the Company’s products. The Company recognizes revenue on product sales when the Customer obtains control of the Company's product, which occurs at delivery for wholesale distributors and generally for specialty pharmacies. Product revenues are recorded net of applicable reserves for variable consideration, including discounts and allowances. Free Goods Program – From time to time, the Company offers programs to potential new patients that allow them to obtain free goods (prescription fills) from a pharmacy. T he Company excludes such amounts from both gross and net revenue. The cost of product associated with the free goods program is included in cost of goods sold. Reserves for Variable Consideration — Revenues from product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established. Components of variable consideration include trade discounts and allowances, product returns, provider chargebacks and discounts, government rebates, payor rebates, and other incentives, such as voluntary patient assistance, and other allowances that are offered within contracts between the Company and its Customers, payors, and other indirect customers relating to the Company’s sale of its products. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and result in a reduction of accounts receivable or establishment of a current liability. Significant judgments are required in making these estimates. Where appropriate, these estimates take into consideration a range of possible outcomes which are probability-weighted in accordance with the expected value method in Topic 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reduce recognized revenue to the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts. The amount of variable consideration which is included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under the contract will not occur in a future period. The Company’s analysis also contemplates application of the constraint in accordance with the guidance, under which it determined a material reversal of revenue would not occur in a future period for the estimates detailed below as of March 31, 2020 and, therefore, the transaction price was not reduced further during the three months ended March 31, 2020. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net revenue — commercial product sales and earnings in the period such variances become known. Trade Discounts and Allowances — The Company generally provides Customers with discounts which include incentives, such as prompt pay discounts, that are explicitly stated in the Company’s contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, the Company compensates (through trade discounts and allowances) its Customers for sales order management, data, and distribution services. However, the Company has determined such services received to date are not distinct from the Company’s sale of products to the Customer and, therefore, these payments have been recorded as a reduction of revenue and as a reduction to accounts receivable, net. Product Returns — Consistent with industry practice, the Company generally offers Customers a right of return for unopened product that has been purchased from the Company for a period beginning six months prior to and ending 12 months after its expiration date , which lapses upon shipment to a patient. The Company estimates the amount of its product sales that may be returned by its Customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized, as well as reductions to accounts receivable, net. The Company currently estimates product returns using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. The Company’s current return reserve percentage is estimated to be in the single-digits. Adjustments to the returns reserve have been made in the past and may be necessary in the future based on revised estimates to our assumptions. Provider Chargebacks and Discounts — Chargebacks for fees and discounts to providers represent the estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at prices lower than the list prices charged to Customers who directly purchase the product from the Company. Customers charge the Company for the difference between what they pay for the product and the ultimate selling price to the qualified healthcare providers. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is recorded in accrued expenses and other current liabilities. Chargeback amounts are generally determined at the time of resale to the qualified healthcare provider by Customers, and the Company generally issues credits for such amounts within a few weeks of the Customer’s notification to the Company of the resale. Reserves for chargebacks consist of credits that the Company expects to issue for units that remain in the distribution channel inventories at each reporting period-end that the Company expects will be sold to qualified healthcare providers, and chargebacks that Customers have claimed, but for which the Company has not yet issued a credit. Government Rebates — The Company is subject to discount obligations under Medicare and state Medicaid programs. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities. Estimates around Medicaid have historically required significant judgement due to timing lags in receiving invoices for claims from states. For Medicare, the Company also estimates the number of patients in the prescription drug coverage gap for whom the Company will owe an additional liability under the Medicare Part D program. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Payor Rebates — The Company contracts with certain private payor organizations, primarily insurance companies and pharmacy benefit managers, for the payment of rebates with respect to utilization of its products. The Company estimates these rebates, including estimates for product that has been recognized as revenue, but which remains in the distribution channel, and records such estimates in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities. Other Incentives — Other incentives which the Company offers include voluntary patient support programs, such as the Company's co-pay assistance program, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with the product that has been recognized as revenue, but remains in the distribution channel inventories at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included in accrued expenses and other current liabilities.
Revenue Recognition- Net Revenue - Collaborations and Services	Revenue Recognition — Revenue — Collaborations and Services — The Company enters into licensing or research agreements under which the Company licenses certain rights to its product candidates to third parties or conducting research services to third parties. The terms of these arrangements may include , but are not limited to payment to the Company of one or more of the following: up-front license fees; development, regulatory, and commercial milestone payments; payments for manufacturing commercial and clinical supply services the Company provides; and royalties on net sales of licensed products and sublicenses of the rights. As part of the accounting for these arrangements, the Company must develop assumptions that require judgment such as determining the performance obligation in the contract and determining the stand-alone selling price for each performance obligation identified in the contract. If an arrangement has multiple performance obligations, the allocation of the transaction price is determined from observable market inputs, and the Company uses key assumptions to determine the stand-alone selling price, which may include development timelines, reimbursement rates for personnel costs, discount rates, and probabilities of technical and regulatory success. Revenue is recognized based on the measurement of progress as the performance obligation is satisfied and consideration received that does not meet the requirements to satisfy the revenue recognition criteria is recorded as deferred revenue. Current deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months. Amounts that the Company expects will not be recognized within the next 12 months are classified as long-term deferred revenue. For further information see Note 7 – . The Company recognizes upfront license payments as revenue upon delivery of the license only if the license is determined to be a separate unit of accounting from the other undelivered performance obligations. The undelivered performance obligations typically include manufacturing or development services or research and/or steering committee services. If the license is not considered as a distinct performance obligation, then the license and other undelivered performance obligations would be evaluated to determine if such should be accounted for as a single unit of accounting. If concluded to be a single performance obligation, the transaction price for the single performance obligation is recognized as revenue over the estimated period of when the performance obligation is satisfied. Whenever the Company determines that an arrangement should be accounted for over time, the Company determines the period over which the performance obligations will be performed, and revenue will be recognized over the period the Company is expected to complete its performance obligations. Significant management judgment is required in determining the level of effort required under an arrangement and the period over which the Company is expected to complete its performance obligations under an arrangement. The Company’s collaboration agreements typically entitle the Company to additional payments upon the achievement of development, regulatory and sales milestones. If the achievement of a milestone is considered probable at the inception of the collaboration, the related milestone payment is included with other collaboration consideration, such as upfront fees and research funding, in the Company’s revenue calculation. If these milestones are not considered probable at the inception of the collaboration, the milestones will typically be recognized in one of two ways depending on the timing of when the milestone is achieved. If the milestone is improbable at inception and subsequently deemed probable of achievement, such will be added to the transaction price, resulting in a cumulative adjustment to revenue. If the milestone is achieved after the performance period has completed and all performance obligations have been delivered, the Company will recognize the milestone payment as revenue in its entirety in the period the milestone was achieved. The Company’s collaborative agreements, for accounting purposes, represent contracts with customers and therefore are not subject to accounting literature on collaborative agreements. The Company grants licenses to its intellectual property, supplies raw materials or finished goods and provides research and development services, all of which are outputs of the Company’s ongoing activities, in exchange for consideration. The Company does not develop assets jointly with collaboration partners, and does not share in significant risks of their development or commercialization activities. Accordingly, the Company concluded that its collaborative agreements must be accounted for pursuant to Topic 606, Revenue from Contracts with Customers. For collaboration agreements that allow collaboration partners to select additional optioned products or services, the Company evaluates whether such options contain material rights (i.e., have exercise prices that are discounted compared to what the Company would charge for a similar product or service to a new collaboration partner). The exercise price of these options includes a combination of licensing fees, event-based milestone payments and royalties. When these amounts in aggregate are not offered at a discount that exceeds discounts available to other customers, the Company concludes the option does not contain a material right, and therefore is not included in the transaction price at contract inception. Rather, the Company evaluates grants of additional licensing rights upon option exercises to determine whether such should be accounted for as separate contracts. The Company concluded there is no material right in these options. The Company follows detailed accounting guidance in measuring revenue and certain judgments affect the application of its revenue policy. For example, in connection with its existing collaboration agreements, the Company has recorded on its condensed consolidated balance sheets short-term and long-term deferred revenue based on its best estimate of when such revenue will be recognized. Short-term deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months. Amounts that the Company expects will not be recognized within the next 12 months are classified as long-term deferred revenue. However, this estimate is based on the Company’s current project development plan and, if the development plan should change in the future, the Company may recognize a different amount of deferred revenue over the next 12-month period.
Milestone Payments	Milestone Payments — At the inception of each arrangement that includes development milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the customer, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as, or when, the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company will re-evaluate the probability of achievement of such development milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration, other revenue, and earnings in the period of adjustment.
Cost of Goods Sold	Cost of Goods Sold — Cost of goods sold includes material, labor costs and manufacturing overhead. Cost of goods sold also includes a significant component of current period manufacturing costs in excess of costs capitalized into inventory (excess capacity costs). These costs, in addition to the impact of the annual revaluation of inventory to standard costs, and write-offs of inventory are recorded as expenses in the period in which they are incurred, rather than as a portion of inventory costs. The cost of goods sold excludes the cost of insulin purchased under our Insulin Supply Agreement (see Note 10 – ). All insulin inventory on hand was written off and the full purchase commitment contract to purchase future insulin was accrued as a recognized loss on purchase commitments as of the end of 2015.
Cash and Cash Equivalents and Restricted Cash	Cash and Cash Equivalents and Restricted Cash —The Company considers all highly liquid investments with original or remaining maturities of 90 days or less at the time of purchase, that are readily convertible into cash to be cash equivalents. As of March 31, 2020 and December 31, 2019, cash equivalents were comprised of money market accounts with maturities less than 90 days from the date of purchase. The Company records restricted cash when cash and cash equivalents are restricted as to withdrawal or usage. The Company presents amounts of restricted cash that will be available for use within 12 months of the reporting date as restricted cash in current assets. Restricted cash amounts that will not be available for use in the Company’s operations within 12 months of the reporting date are presented as restricted cash in long term assets. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported on the consolidated balance sheets that sum to amounts reported on the consolidated statement of cash flows (in thousands): March 31, 2020 December 31, 2019 Cash and cash equivalents $ 38,868 $ 29,906 Restricted cash 316 316 Total cash, cash equivalents, and restricted cash $ 39,184 $ 30,222
Short-term Investments	Short-term Investments —The Company’s short-term investments consist of U.S. Treasury securities stated at amortized cost which the Company intends to hold until maturity. Those with maturities less than 12 months are included in short-term investments and any investments with maturities in excess of twelve months are included in long-term investments in our condensed consolidated balance sheets. As of March 31, 2020, the Company did not hold any short-term investments nor did it record any material gains or losses on short-term investment securities during the three months ended March 31, 2020.
Concentration of Credit Risk	Concentration of Credit Risk — Financial instruments that potentially subject the Company to concentration of credit risk consist of cash and cash equivalents and short-term investments. Cash and cash equivalents are held in high credit quality institutions. Cash equivalents consist of interest-bearing money market accounts and U.S. Treasury securities, which are regularly monitored by management.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts — Accounts receivable are recorded at the invoiced amount and are not interest bearing. Accounts receivable are presented net of an allowance for doubtful accounts if there are estimated losses resulting from the inability of its customers to make required payments. The Company makes ongoing assumptions relating to the collectability of its accounts receivable in its calculation of the allowance for doubtful accounts. Accounts receivable are also presented net of an allowance for product returns and trade discounts and allowances because the Company’s customers have the right of setoff for these amounts against the related accounts receivable.
Pre Launch Inventory	Pre-Launch Inventory — An improvement to the manufacturing process for the Company’s primary excipient FDKP was demonstrated to be viable and management expects to realize an economic benefit in the future as a result of such process improvement. Accordingly, the Company is required to assess whether to capitalize inventory costs related to such excipient prior to regulatory approval of the new supplier and the improved manufacturing process. In doing so, management must consider a number of factors in order to determine the amount of inventory to be capitalized, including the historical experience of achieving regulatory approvals for the Company’s manufacturing process, feedback from regulatory agencies on the changes being effected and the amount of inventory that is likely to be used in commercial production. The shelf life of the excipient will be determined as part of the regulatory approval process; in the interim, the Company must assess the available stability data to determine whether there is likely to be adequate shelf life to support anticipated future sales occurring beyond the expected approval date of the new raw material. If management is aware of any specific material risks or contingencies other than the normal regulatory review and approval process, or if the criteria for capitalizing inventory produced prior to regulatory approval are otherwise not met, the Company would not capitalize such inventory costs, choosing instead to recognize such costs as a research and development expense in the period incurred.
Inventories	Inventories — Inventories are stated at the lower of cost or net realizable value. The Company determines the cost of inventory using the first-in, first-out, or FIFO, method. The Company capitalizes inventory costs associated with the Company’s products based on management’s judgment that future economic benefits are expected to be realized; otherwise, such costs are expensed as incurred as cost of goods sold. The Company periodically analyzes its inventory levels to identify inventory that may expire or has a cost basis in excess of its estimated realizable value and writes down such inventories, as appropriate. In addition, the Company’s products are subject to strict quality control and monitoring which the Company performs throughout the manufacturing process. If certain batches or units of product no longer meet quality specifications or may become obsolete or are forecasted to become obsolete due to expiration, the Company will record a charge to write down such unmarketable inventory to its estimated net realizable value. The Company analyzes its inventory levels to identify inventory that may expire or has a cost basis in excess of its estimated realizable value. The Company performs an assessment of projected sales and evaluates the lower of cost or net realizable value and the potential excess inventory on hand at the end of each reporting period.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets — The Company evaluates long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. Assets are considered to be impaired if the carrying value may not be recoverable. If the Company believes an asset to be impaired, the impairment recognized is the amount by which the carrying value of the asset exceeds the fair value of the asset. Fair value is determined using the market, income or cost approaches as appropriate for the asset. Any write-downs are treated as permanent reductions in the carrying amount of the asset and recognized as an operating loss. In August 2019, the Company recorded a $1.5 million commitment asset related to the future funding commitments of the MidCap Credit Facility. An assessment was performed as of March 31, 2020 to determine if the Company was on target to achieve certain milestone conditions that are required in order for the Company to access further borrowings under the MidCap Credit Facility. As a result of this assessment, a $1.5 million asset impairment was recognized for the three months ended March 31, 2020. See Note 6 – Borrowings for further information on the MidCap Credit Facility.
Recognized Loss on Purchase Commitments	Recognized Loss on Purchase Commitments — The Company assesses whether losses on long term purchase commitments should be accrued. Losses that are expected to arise from firm, non-cancellable, commitments for the future purchases are recognized unless recoverable. When making the assessment, the Company also considers whether it is able to renegotiate with its vendors. The recognized loss on purchase commitments is reduced as inventory items are received. If, subsequent to an accrual, a purchase commitment is successfully renegotiated, the gain is recognized in the Company’s condensed consolidated statement of operations. The liability balance of the recognized loss on insulin purchase commitments was $90.2 million and $92.0 million as of March 31, 2020 and December 31, 2019, respectively. No new contracts were identified in the first quarter of 2020 that required a new loss on purchase commitment accrual.
Milestone Rights Liability	Milestone Rights Liability — On July 1, 2013, in conjunction with the execution of a financing facility with Deerfield Private Design Fund II L.P. and Deerfield Private Design International I L.P. , the Company issued to Deerfield Private Design Fund II, L.P. and Horizon Santé FLML SÁRL (the “Milestone Purchasers”) certain rights to receive payments of up to $90.0 million, of which $70.0 million remains payable as of March 31, 2020 upon the occurrence of specified strategic and sales milestones, including the achievement of specified net sales figures (the “Milestone Rights”). The Company analyzed the Milestone Rights and determined that they did not meet the definition of a freestanding derivative. Since the Company has not elected to apply the fair value option to the Milestone Rights, the Company recorded them at their estimated initial fair value and accounted for the Milestone Rights as a liability. The initial fair value estimate of the Milestone Rights was calculated using the income approach in which the cash flows associated with the specified contractual payments were adjusted for both the expected timing and the probability of achieving the milestones and discounted to present value using a selected market discount rate. The expected timing and probability of achieving the milestones was developed with consideration given to both internal data, such as progress made to date and assessment of criteria required for achievement, and external data, such as market research studies. The discount rate was selected based on an estimation of required rate of returns for similar investment opportunities using available market data. The Milestone Rights liability will be remeasured as the specified milestone events are achieved. Specifically, as each milestone event is achieved, the portion of the initially recorded Milestone Rights liability that pertains to the milestone event being achieved, will be remeasured to the amount of the specified related milestone payment. The resulting change in the balance of the Milestone Rights liability due to remeasurement will be recorded in the Company’s consolidated statements of operations as interest expense. Furthermore, the Milestone Rights liability will be reduced upon the settlement of each milestone payment. As a result, each milestone payment would be effectively allocated between a reduction of the recorded Milestone Rights liability and an expense representing a return on a portion of the Milestone Rights liability paid to the investor for the achievement of the related milestone event (see Note 6 – Borrowings
Fair Value of Financial Instruments	Fair Value of Financial Instruments — The Company applies various valuation approaches in determining the fair value of its financial assets and liabilities within a hierarchy that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and are developed based on the best information available in the circumstances. The fair value hierarchy is broken down into three levels based on the source of inputs as follows: Level 1 — Quoted prices for identical instruments in active markets. Level 2 — Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable. Level 3 — Significant inputs to the valuation model are unobservable.
Income Taxes	Income Taxes — The provisions for federal, foreign, state and local income taxes are calculated on pre-tax income based on current tax law and include the cumulative effect of any changes in tax rates from those used previously in determining deferred tax assets and liabilities. Deferred income tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the year in which the temporary differences are expected to be recovered or settled. A valuation allowance is recorded to reduce net deferred income tax assets to amounts that are more likely than not to be realized. Income tax positions are considered for uncertainty. The Company believes that its income tax filing positions and deductions will be sustained on audit and does not anticipate any adjustments that will result in a material change to its financial position. Therefore, no liabilities for uncertain income tax positions have been recorded. If a tax position does not meet the minimum statutory threshold to avoid payment of penalties, the Company recognizes an expense for the amount of the penalty in the period the tax position is claimed in the tax return of the Company. The Company recognizes interest accrued related to unrecognized tax benefits in income tax expense, if any. Penalties, if probable and reasonably estimable, are recognized as a component of income tax expense.
Contingencies	Contingencies — The Company records a loss contingency for a liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. These accruals represent management’s best estimate of probable loss. Disclosure also is provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. On a quarterly basis, the Company reviews the status of each significant matter and assesses its potential financial exposure. Significant judgment is required in both the determination of probability and the determination as to whether an exposure is reasonably estimable. Because of uncertainties related to these matters, accruals are based only on the best information available at the time. As additional information becomes available, the Company reassesses the potential liability related to pending claims and litigation and may revise its estimates.
Stock-Based Compensation	Stock-Based Compensation — Share-based payments to employees, including grants of stock options, restricted stock units, performance-based awards and the compensatory elements of employee stock purchase plans, are recognized in the condensed consolidated statements of operations based upon the fair value of the awards at the grant date. The Company uses the Black-Scholes option valuation model to estimate the grant date fair value of employee stock options and the compensatory elements of employee stock purchase plans. Restricted stock units are valued based on the market price on the grant date. The Company evaluates stock awards with performance conditions as to the probability that the performance conditions will be met and estimates the date at which the performance conditions will be met in order to properly recognize stock-based compensation expense over the requisite service period.
Clinical Trial Expenses	Clinical Trial Expenses — Clinical trial expenses, which are primarily reflected in research and development expenses in the accompanying condensed consolidated statements of operations, result from obligations under contracts with vendors, consultants and clinical site agreements in connection with conducting clinical trials.
Net Income (Loss) Per Share of Common Stock	Net Income (Loss) Per Share of Common Stock — Basic net income or loss per share excludes dilution for potentially dilutive securities and is computed by dividing net income or loss by the weighted average number of common shares outstanding during the period. Diluted net income or loss per share reflects the potential dilution under the treasury method that could occur if securities or other contracts to issue common stock were exercised or converted into common stock. For periods where the Company has presented a net loss, potentially dilutive securities are excluded from the computation of diluted net loss per share as they would be anti-dilutive. The computation of basic and diluted net loss per share for the three months ended March 31, 2020 and 2019 excludes the common stock equivalents of the following potentially dilutive securities because their inclusion would be anti-dilutive while the Company is in a net loss position: Three months ended March 31, 2020 2019 Vesting of restricted stock units 522,021 1,314,218 Employee stock purchase plan 144,088 141,568 Exercise of common stock options 14,014,315 10,846,738 Conversion of 2024 convertible notes into common stock 1,666,667 3,629,627 Conversion of Mann Group convertible note into common stock 14,000,000 21,909,541 Exercise of common stock warrants 31,851 31,851 Exercise of warrants associated with Midcap Credit Facility 1,171,614 — Exercise of warrants associated with public offering 7,250,000 26,666,667 Exercise of warrants associated with direct placement — 14,000,000 Total shares 38,800,556 78,540,210
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards — In June 2016, the FASB issued ASU No. 2016-13, The Company adopted this standard as of January 1, 2020. This update introduces the current expected credit loss (CECL) model, which requires an entity to measure credit losses for certain financial instruments and financial assets, including trade receivables. Under this update, on initial recognition and at each reporting period, an entity is required to recognize an allowance that reflects the entity’s current estimate of credit losses expected to be incurred over the life of the financial instrument. The adoption of this standard did not have a material impact on the Company's condensed consolidated financial statements.
Recently Issued Accounting Standards	Recently Issued Accounting Standards — From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) or other standard setting bodies that are adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s condensed consolidated financial position or results of operations upon adoption. In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740) In November 2018, the FASB issued ASU No. 2018-18, Collaborative Arrangements (Topic 808)

Description of Business and S_3

Description of Business and Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported on the consolidated balance sheets that sum to amounts reported on the consolidated statement of cash flows (in thousands): March 31, 2020 December 31, 2019 Cash and cash equivalents $ 38,868 $ 29,906 Restricted cash 316 316 Total cash, cash equivalents, and restricted cash $ 39,184 $ 30,222
Schedule of Potentially Dilutive Common Stock Equivalent Securities	The computation of basic and diluted net loss per share for the three months ended March 31, 2020 and 2019 excludes the common stock equivalents of the following potentially dilutive securities because their inclusion would be anti-dilutive while the Company is in a net loss position: Three months ended March 31, 2020 2019 Vesting of restricted stock units 522,021 1,314,218 Employee stock purchase plan 144,088 141,568 Exercise of common stock options 14,014,315 10,846,738 Conversion of 2024 convertible notes into common stock 1,666,667 3,629,627 Conversion of Mann Group convertible note into common stock 14,000,000 21,909,541 Exercise of common stock warrants 31,851 31,851 Exercise of warrants associated with Midcap Credit Facility 1,171,614 — Exercise of warrants associated with public offering 7,250,000 26,666,667 Exercise of warrants associated with direct placement — 14,000,000 Total shares 38,800,556 78,540,210

Accounts Receivable (Tables)

Accounts Receivable (Tables)	3 Months Ended
	Mar. 31, 2020
Receivables [Abstract]
Schedule of Accounts Receivable, Net	Accounts receivable, net consists of the following (in thousands): March 31, 2020 December 31, 2019 Accounts receivable, gross $ 8,393 $ 6,925 Wholesaler distribution fees and prompt pay discounts (1,458 ) (1,767 ) Reserve for returns (1,903 ) (1,645 ) Accounts receivable, net $ 5,032 $ 3,513

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2020
Inventory Disclosure [Abstract]
Components of Inventory	Inventories consist of the following (in thousands): March 31, 2020 December 31, 2019 Raw materials $ 1,643 $ 1,751 Work-in-process 495 1,432 Finished goods 1,093 972 Total inventory $ 3,231 $ 4,155

Property and Equipment (Tables)

Property and Equipment (Tables)	3 Months Ended
	Mar. 31, 2020
Property Plant And Equipment [Abstract]
Property and Equipment, Net	Property and equipment consists of the following (in thousands): Estimated Useful Life (Years) March 31, 2020 December 31, 2019 Land — $ 875 $ 875 Buildings 39-40 17,389 17,389 Building improvements 5-40 37,543 37,543 Machinery and equipment 3-15 54,978 54,982 Furniture, fixtures and office equipment 5-10 3,005 3,005 Computer equipment and software 3 8,319 8,234 Construction in progress — 176 114 122,285 122,142 Less accumulated depreciation (95,768 ) (95,364 ) Total property and equipment, net $ 26,517 $ 26,778
Depreciation Expense Related to Property and Equipment	Depreciation expense related to property and equipment was as follows (in thousands): Three Months Ended March 31, 2020 2019 Depreciation Expense $ 443 $ 367

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	3 Months Ended
	Mar. 31, 2020
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities were comprised of the following (in thousands): March 31, 2020 December 31, 2019 Salary and related expenses $ 10,217 $ 8,835 Discounts and allowances for commercial product sales 3,534 3,162 Deferred lease liability 1,415 1,433 Milestone Rights liability — current 1,337 — Professional fees 314 620 Sales and marketing services 309 147 Accrued interest 337 409 Other 863 1,298 Total accrued expenses and other current liabilities $ 18,326 $ 15,904

Borrowings (Tables)

Borrowings (Tables)	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Summary of Carrying Amount of Borrowings	Carrying amount of borrowings consist of the following (in thousands): March 31, 2020 December 31, 2019 Mann Group promissory notes $ 70,022 $ 70,020 Midcap Credit Facility 38,893 38,851 Senior notes (2020 notes and 2024 convertible notes) 10,101 10,028 Total debt — net carrying amount $ 119,016 $ 118,899
Schedule of Line of Credit Facility Debt and Key Terms	The following table provides a summary of the Company’s debt and key terms: Amount Due Terms March 31, 2020 December 31, 2019 Annual Interest Rate Maturity Date Conversion Price Mann Group convertible note $35.0 million (plus $1.6 million accrued interest paid-in-kind) $35.0 million (plus $1.0 million accrued interest paid-in-kind) 7.00% November 2024 $2.50 per share Mann Group non- convertible note $35.1 million (plus $1.6 million accrued interest paid-in-kind) $35.1 million (plus $1.0 million accrued interest paid-in-kind) 7.00% November 2024 N/A MidCap Credit Facility $40.0 million $40.0 million one-month LIBOR (2% floor) plus 6.75% August 2024 N/A 2024 convertible notes $5.0 million $5.0 million 5.75% November 2024 $3.00 per share June 2020 note $2.6 million $2.6 million — June 2020 N/A December 2020 note $2.6 million $2.6 million — December 2020 N/A
Schedule of Maturities of Our Borrowings	The maturities of our borrowings as of March 31, 2020 are as follows (in thousands): Amounts 2020 $ 5,262 2021 4,444 2022 13,333 2023 13,333 2024 83,940 Thereafter — Total principal payments 120,312 Unamortized discount (450 ) Debt issuance costs (846 ) Total debt — net carrying amount $ 119,016
Schedule of Amortization of Premium and Accretion of Debt Issuance Costs	Amortization of the premium and accretion of debt issuance costs related to all borrowings for the three months ended March 31, 2020 and 2019 are as follows (in thousands): Three Months Ended March 31, 2020 2019 Amortization of debt discount $ 89 $ 72 Accretion expense — debt issuance cost (27 ) (22 ) Amortization of debt premium — (95 )

Collaborations and Licensing _2

Collaborations and Licensing Arrangements (Tables)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Revenue from Collaboration and Services	Revenue from collaborations and services for the three months ended March 31, 2020 and 2019 are as follows (in thousands): Three Months Ended March 31, 2020 2019 UT License Agreement $ 7,978 $ 7,615 UT Research Agreement 158 4,658 Receptor CLA 62 62 Cipla distribution agreement 37 37 Total revenue from collaborations and services $ 8,235 $ 12,372

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurement of Debt Instruments Based on Discounted Cash Flow Model and Sensitive to Change in Yield	The fair value measurement of debt instruments is based on a discounted cash flow model and is sensitive to the change in yield (Level 3 in the fair value hierarchy): Hypothetical Change in Yield Hypothetical Change in Notes Payable Yield % Change Hypothetical Yield FV of Notes FV $ Change % Change (in millions) Mann Group promissory notes: (with conversion feature) 35.0 % 2 % 37.0 % $ 38.0 $ 36.4 $ (1.6 ) -4.2 % 35.0 % -2 % 33.0 % $ 38.0 $ 39.8 $ 1.8 4.7 % 35.0 % 4 % 39.0 % $ 38.0 $ 34.8 $ (3.2 ) -8.4 % 35.0 % -4 % 31.0 % $ 38.0 $ 41.8 $ 3.8 10.0 % Senior notes: (with conversion feature) 35.0 % 2 % 37.0 % $ 7.6 $ 7.5 $ (0.1 ) -1.3 % 35.0 % -2 % 33.0 % $ 7.6 $ 7.8 $ 0.2 2.6 % 35.0 % 4 % 39.0 % $ 7.6 $ 7.4 $ (0.2 ) -2.6 % 35.0 % -4 % 31.0 % $ 7.6 $ 7.9 $ 0.3 3.9 % MidCap Credit Facility 17.0 % 1 % 18.0 % $ 35.8 $ 35.1 $ (0.7 ) -2.0 % 17.0 % -1 % 16.0 % $ 35.8 $ 36.6 $ 0.8 2.2 % 17.0 % 2 % 19.0 % $ 35.8 $ 34.3 $ (1.5 ) -4.2 % 17.0 % -2 % 15.0 % $ 35.8 $ 37.4 $ 1.6 4.5 %
Fair Value of Financial Instruments	The following tables set forth the fair value of the Company’s financial instruments (in millions): March 31, 2020 Carrying Value Significant Unobservable Inputs (Level 3) Fair Value Financial liabilities: MidCap Credit Facility $ 38.9 $ 35.8 $ 35.8 2024 convertible notes 5.0 3.1 3.1 June 2020 note 2.6 2.4 2.4 December 2020 note 2.5 2.1 2.1 Mann Group promissory notes 70.0 38.0 38.0 Milestone rights 7.3 14.3 14.3 Total financial liabilities $ 126.3 $ 95.7 $ 95.7 December 31, 2019 Carrying Value Significant Unobservable Inputs (Level 3) Fair Value Financial liabilities: MidCap Credit Facility $ 38.9 $ 40.0 $ 40.0 2024 convertible notes 5.0 3.7 3.7 June 2020 note 2.5 2.3 2.3 December 2020 note 2.5 2.0 2.0 Mann Group promissory notes 70.0 46.2 46.2 Milestone rights 7.3 16.4 16.4 Total financial liabilities $ 126.2 $ 110.6 $ 110.6

Stock-Based Compensation Expe_2

Stock-Based Compensation Expense (Tables)	3 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation Expense Recognized in Accompanying Condensed Consolidated Statements of Operations	Total stock-based compensation expense recognized in the accompanying condensed consolidated statements of operations for the three months ended March 31, 2020 and 2019 was as follows (in thousands): Three Months Ended March 31, 2020 2019 Restricted stock units and options $ 1,066 $ 883 Employee stock purchase plan 62 116 Total stock compensation expense $ 1,128 $ 999

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Annual Purchase Requirements under Amended Contract	In August 2019, the Company and Amphastar amended the Insulin Supply Agreement to extend the term to 2026 and to restructure the annual purchase commitments. As of March 31, 2020, the annual purchase requirements under the amended contract are as follows: Minimum Commitment 2020 € 6.6 million 2021 € 6.6 million 2022 € 8.5 million 2023 € 10.8 million 2024 € 14.6 million 2025 € 15.5 million 2026 € 19.4 million
Schedule of Future Minimum Office And Vehicle Lease Payments	Future minimum office and vehicle lease payments as of March 31, 2020 and December 31, 2019, are as follows (in thousands): March 31, 2020 December 31, 2019 2020 $ 1,105 $ 1,470 2021 1,500 1,500 2022 1,241 1,241 2023 88 88 Total $ 3,934 $ 4,299

Description of Business and S_4

Description of Business and Significant Accounting Policies - Additional Information (Detail)	Aug. 06, 2019USD ($)	Aug. 31, 2019USD ($)	Mar. 31, 2020USD ($)SegmentContract	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jul. 01, 2013USD ($)
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Accumulated deficit			$ (3,001,225,000)	$ (2,991,903,000)
Principal amount			120,300,000
Cash and cash equivalents			$ 38,868,000	29,906,000
Number of operating segment | Segment			1
Short-term investments			$ 0	19,978,000
Asset impairment			1,521,000
Remaining milestone rights liability			7,300,000	7,300,000
Liabilities for uncertain income tax positions			0
Commitment Asset | Other Expense
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Asset impairment			1,500,000
Insulin
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Loss on purchase commitments			$ 90,200,000		$ 92,000,000
Loss on purchase commitments, number of new contracts recognized | Contract			0
Maximum | AFREZZA product sales
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sales return right following product expiration in months			12 months
Minimum | AFREZZA product sales
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Sales return right following product expiration in months			6 months
Facility Financing Obligation | Deerfield
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Remaining milestone rights liability			$ 7,300,000	7,300,000
MidCap Credit Facility
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Principal amount			40,000,000	40,000,000
Principal amount	$ 75,000,000	$ 75,000,000
Amount outstanding				$ 40,000,000
Amount available under credit facility		35,000,000
Minimum cash covenant	15,000,000
Commitment asset		1,500,000
MidCap Credit Facility | Commitment Asset
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Asset impairment			1,500,000
MidCap Credit Facility | Tranche 2
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Amount available under credit facility		10,000,000
Debt instrument, minimum target net revenue	30,000,000	30,000,000
Minimum cash covenant			15,000,000
MidCap Credit Facility | Tranche 3
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Amount available under credit facility		$ 25,000,000
Minimum cash covenant	$ 20,000,000		20,000,000
Milestone Rights Liability | Deerfield
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Contingent liability remain payable			$ 70,000,000
Milestone Rights Liability | Maximum | Deerfield
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Contingent liability for milestone payments						$ 90,000,000

Description of Business and S_5

Description of Business and Significant Accounting Policies - Additional Information (Detail 1)	Mar. 31, 2020
Collaborations and services | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2020-04-01
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Remaining performance obligation, expected timing of satisfaction, period	12 months

Schedule of Reconciliation of C

Schedule of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Cash and cash equivalents	$ 38,868	$ 29,906
Restricted cash	316	316
Total cash, cash equivalents, and restricted cash	$ 39,184	$ 30,222	$ 35,057	$ 71,684

Schedule of Potentially Dilutiv

Schedule of Potentially Dilutive Common Stock Equivalent Securities (Detail) - shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	38,800,556	78,540,210
Vesting of Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	522,021	1,314,218
Conversion of 2024 Convertible Notes into Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	1,666,667	3,629,627
Exercise of Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	31,851	31,851
Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	144,088	141,568
Conversion of Mann Group Convertible Note into Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	14,000,000	21,909,541
Exercise of Common Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	14,014,315	10,846,738
Exercise of Warrants Associated with Midcap Credit Facility
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	1,171,614
Exercise of Warrants Associated with Public Offering
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share	7,250,000	26,666,667
Exercise of Warrants Associated with Direct Placement
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share		14,000,000

Schedule of Accounts Receivable

Schedule of Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Accounts receivable, gross	$ 8,393	$ 6,925
Wholesaler distribution fees and prompt pay discounts	(1,458)	(1,767)
Reserve for returns	(1,903)	(1,645)
Accounts receivable, net	$ 5,032	$ 3,513

Accounts Receivable - Additiona

Accounts Receivable - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020Distributor
Receivables [Abstract]
Number of wholesale distributors	3
Percentage of accounts receivable from major wholesale distributors	91.00%
Percentage of gross sales from major wholesale distributors	92.00%

Inventories - Components of Inv

Inventories - Components of Inventory (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 1,643	$ 1,751
Work-in-process	495	1,432
Finished goods	1,093	972
Total inventory	$ 3,231	$ 4,155

Inventories - Additional Inform

Inventories - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Inventory [Line Items]
Write-off of inventory	$ 496,000	$ 0
Pre-launch Inventory
Inventory [Line Items]
Raw materials inventory	$ 800,000		$ 800,000

Property and Equipment, Net (De

Property and Equipment, Net (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 122,285	$ 122,142
Less accumulated depreciation	(95,768)	(95,364)
Total property and equipment, net	26,517	26,778
Land
Property Plant And Equipment [Line Items]
Property and equipment - gross	875	875
Buildings
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 17,389	17,389
Buildings | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	39 years
Buildings | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	40 years
Building Improvements
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 37,543	37,543
Building Improvements | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Building Improvements | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	40 years
Machinery and Equipment
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 54,978	54,982
Machinery and Equipment | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	3 years
Machinery and Equipment | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	15 years
Furniture, fixtures and office equipment
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 3,005	3,005
Furniture, fixtures and office equipment | Minimum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	5 years
Furniture, fixtures and office equipment | Maximum
Property Plant And Equipment [Line Items]
Estimated Useful Life (Years)	10 years
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 8,319	8,234
Estimated Useful Life (Years)	3 years
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment - gross	$ 176	$ 114

Depreciation Expense Related to

Depreciation Expense Related to Property and Equipment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Property Plant And Equipment [Abstract]
Depreciation Expense	$ 443	$ 367

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accrued Expenses And Other Current Liabilities [Abstract]
Salary and related expenses	$ 10,217	$ 8,835
Discounts and allowances for commercial product sales	3,534	3,162
Deferred lease liability	1,415	1,433
Milestone Rights liability — current	1,337
Professional fees	314	620
Sales and marketing services	309	147
Accrued interest	337	409
Other	863	1,298
Total accrued expenses and other current liabilities	$ 18,326	$ 15,904

Borrowings - Summary of Carryin

Borrowings - Summary of Carrying Amount of Borrowings (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Mann Group promissory notes	$ 70,022	$ 70,020
Total debt — net carrying amount	119,016	118,899
MidCap Credit Facility
Debt Instrument [Line Items]
Credit Facility	38,893	38,851
2020 Notes and 2024 Convertible Notes
Debt Instrument [Line Items]
Senior notes	$ 10,101	$ 10,028

Borrowings - Schedule of Line o

Borrowings - Schedule of Line of Credit Facility Debt and Key Terms (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Amount Due	$ 120.3
5.75% 2024 Convertible Notes
Debt Instrument [Line Items]
Annual interest rate	5.75%
Maturity date	Nov. 30, 2024
Amount Due	$ 5	$ 5
June 2020 Note
Debt Instrument [Line Items]
Maturity date	Jun. 30, 2020
Amount Due	$ 2.6	2.6
December 2020 Note
Debt Instrument [Line Items]
Maturity date	Dec. 31, 2020
Amount Due	$ 2.6	2.6
The Mann Group L L C | Convertible Promissory Note
Debt Instrument [Line Items]
Annual interest rate	7.00%
Maturity date	Nov. 30, 2024
Amount Due	$ 35	35
Accrued interest paid-in-kind	$ 1.6	1
The Mann Group L L C | Non Convertible Promissory Note
Debt Instrument [Line Items]
Annual interest rate	7.00%
Maturity date	Nov. 30, 2024
Amount Due	$ 35.1	35.1
Accrued interest paid-in-kind	$ 1.6	1
MidCap Credit Facility
Debt Instrument [Line Items]
Maturity date	Aug. 31, 2024
Amount Due	$ 40	$ 40
MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Annual interest rate	6.75%
Interest rate floor	2.00%

Borrowings - Schedule of Maturi

Borrowings - Schedule of Maturities of Our Borrowings (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2020	$ 5,262
2021	4,444
2022	13,333
2023	13,333
2024	83,940
Total principal payments	120,312
Unamortized discount	(450)
Debt issuance costs	(846)
Total debt — net carrying amount	$ 119,016	$ 118,899

Borrowings - MidCap Credit Faci

Borrowings - MidCap Credit Facility - Additional Information (Detail)	Aug. 06, 2019USD ($)Installment$ / sharesshares	Dec. 31, 2019USD ($)	Aug. 31, 2019USD ($)$ / shares	Mar. 31, 2020USD ($)
Debt Instrument [Line Items]
Asset impairment				$ 1,521,000
Unamortized debt issuance costs				846,000
Unamortized debt discount				450,000
Tranche One Warrants
Debt Instrument [Line Items]
Warrants to purchase of common stock | shares	1,171,614
Exercise price of warrants | $ / shares	$ 1.11
MidCap Credit Facility
Debt Instrument [Line Items]
Principal amount	$ 75,000,000		$ 75,000,000
Advance of borrowing		$ 25,000,000
Amount available under credit facility			$ 35,000,000
Unamortized debt issuance costs				800,000
Unamortized debt discount				$ 300,000
Credit facility, origination fee	400,000
Minimum cash covenant	$ 15,000,000
Interest on loans increased, percentage	2.00%
Term loan advance percentage of amount drawdown	3.25%
Exercise price of warrants | $ / shares			$ 1.11
MidCap Credit Facility | Between First Anniversary and Prior to Second Anniversary of Closing Date
Debt Instrument [Line Items]
Early termination fees, percentage	2.00%
MidCap Credit Facility | Prior to First Anniversary of Closing Date
Debt Instrument [Line Items]
Early termination fees, percentage	3.00%
MidCap Credit Facility | After Second Anniversary and Prior to Third Anniversary of Closing Date
Debt Instrument [Line Items]
Early termination fees, percentage	1.00%
MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)				6.75%
Interest rate floor				2.00%
MidCap Credit Facility | Minimum
Debt Instrument [Line Items]
Debt Instrument Exit Fee Percentage		6.00%
MidCap Credit Facility | Maximum
Debt Instrument [Line Items]
Debt Instrument Exit Fee Percentage		7.00%
MidCap Credit Facility | Commitment Asset
Debt Instrument [Line Items]
Asset impairment				$ 1,500,000
Tranche 1 | MidCap Credit Facility
Debt Instrument [Line Items]
Advance of borrowing	$ 40,000,000
Debt payable number of equal monthly installments | Installment	36
Debt instrument payment term description	principal on any term loan advance under Tranche 3 is payable beginning on the later of (i) September 1, 2021, and (ii) the first day of the first full calendar month immediately following such term loan advance, in an amount equal to the outstanding term loan advance in respect of Tranche 3 divided by the number of full calendar months remaining before August 1, 2024.
Tranche 1 | MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)	6.75%
Interest rate floor	2.00%
Tranche 2 | MidCap Credit Facility
Debt Instrument [Line Items]
Amount available under credit facility			$ 10,000,000
Debt instrument, minimum target net revenue	$ 30,000,000		30,000,000
Minimum cash covenant				15,000,000
Tranche 3 | MidCap Credit Facility
Debt Instrument [Line Items]
Amount available under credit facility			$ 25,000,000
Debt instrument payment term description	principal on any term loan advance under Tranche 3 is payable beginning on the later of (i) September 1, 2021, and (ii) the first day of the first full calendar month immediately following such term loan advance, in an amount equal to the outstanding term loan advance in respect of Tranche 3 divided by the number of full calendar months remaining before August 1, 2024.
Minimum cash covenant	$ 20,000,000			$ 20,000,000
Tranche 3 | MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)	6.75%
Interest rate floor	2.00%

Borrowings - Senior Note - Addi

Borrowings - Senior Note - Additional Information (Detail)	Aug. 06, 2019d$ / shares	Aug. 31, 2019USD ($)$ / sharesshares	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Principal amount			$ 120,300,000
Bruce & Co.,Inc.
Debt Instrument [Line Items]
Principal amount			18,700
2021 Notes
Debt Instrument [Line Items]
Senior convertible notes outstanding			$ 10,200,000	$ 10,200,000
2021 Notes | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Senior notes, effective interest rate		5.75%
2021 Notes | Privately Negotiated Exchange Agreement | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Repayments of aggregate principal amount		$ 1,500,000
Issuance of common stock to note holders | shares		4,017,857
Exchange price per share | $ / shares		$ 1.12
2024 Convertible Notes
Debt Instrument [Line Items]
No of convertible shares	333.3333
Principal amount per share | $ / shares	$ 1,000
Conversion price of shares | $ / shares	$ 3
Debt default, description			If certain bankruptcy and insolvency-related events of default occur, the principal of, and accrued and unpaid interest on, all of the then outstanding 2024 convertible notes shall automatically become due and payable. If an event of default other than certain bankruptcy and insolvency-related events of defaults occurs and is continuing, the Trustee or the holders of at least 25% in aggregate principal amount of the then-outstanding 2024 convertible notes, by written notice to the Trustee, may declare the 2024 convertible notes due and payable at their principal amount plus any accrued and unpaid interest, and thereupon the Trustee may, at its discretion, proceed to protect and enforce the rights of the holders by the appropriate judicial proceedings. Notwithstanding the foregoing, the Indenture provides that, to the extent the Company elects, the sole remedy for an event of default relating to certain failures by the Company to comply with certain reporting covenants in the Indenture will, for the first 180 days after such event of default, consist exclusively of the right to receive additional interest on the 2024 convertible notes.
Percentage of repurchase price	100.00%
Debt Instrument, redemption description			The Company may elect at its option to cause all or any portion of the 2024 convertible notes to be mandatorily converted in whole or in part at any time prior to the close of business on the business day immediately preceding the maturity date, if the last reported sale price of its common stock equals or exceeds 120% of the conversion price then in effect for at least 10 trading days in any 20 trading day period, ending within five business days prior to the date of the mandatory conversion notice.
Percentage of conversion price equaling stock price	120.00%
Number of trading days | d	10
Consecutive trading days	20 days
2024 Convertible Notes | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Senior notes, effective interest rate	5.75%
Principal amount		$ 5,000,000
Debt instrument, maturity date, description			The 2024 convertible notes will mature on the earlier of (i) November 4, 2024 or (ii) the 91st day after the payment in full of, and termination and discharge of all obligations (other than contingent indemnity obligations) under the MidCap Credit Facility.
2024 Convertible Notes | Privately Negotiated Exchange Agreement | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Senior notes, effective interest rate		5.75%
June 2020 Note [Member] | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Principal amount		$ 2,600,000
Maturity date		Jun. 30, 2020
December 2020 Note [Member] | Bruce & Co.,Inc.
Debt Instrument [Line Items]
Principal amount		$ 2,600,000
Maturity date		Dec. 31, 2020

Borrowings - Mann Group Promiss

Borrowings - Mann Group Promissory Notes - Additional Information (Detail) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Aug. 31, 2019USD ($)$ / sharesshares	Mar. 31, 2020USD ($)shares	Dec. 31, 2019USD ($)shares
Debt Instrument [Line Items]
Common stock, shares issued | shares		213,137,684	211,787,573
Principal amount		$ 120.3
The Mann Group L L C | Convertible Promissory Note
Debt Instrument [Line Items]
Principal amount		35	$ 35
Accrued Paid-in-Kind Interest		$ 1.6	1
Senior notes, effective interest rate		7.00%
Maturity date		Nov. 30, 2024
The Mann Group L L C | Non Convertible Promissory Note
Debt Instrument [Line Items]
Principal amount		$ 35.1	35.1
Accrued Paid-in-Kind Interest		$ 1.6	$ 1
Senior notes, effective interest rate		7.00%
Maturity date		Nov. 30, 2024
The Mann Group L L C | New Loan Arrangement | Convertible Promissory Note
Debt Instrument [Line Items]
Conversion price of shares | $ / shares	$ 2.50
Maturity date	Nov. 3, 2024
No of convertible shares	400
Principal amount per share | $ / shares	$ 1,000
The Mann Group L L C | New Loan Arrangement | Promissory Notes
Debt Instrument [Line Items]
Senior notes, effective interest rate	7.00%
Debt instrument payment term description	quarterly
Debt instrument, date of first required interest payment	Oct. 1, 2019
The Mann Group L L C | New Loan Arrangement | Non Convertible Promissory Note
Debt Instrument [Line Items]
Debt instrument, maturity date, description		The Mann Group non-convertible note will mature on the earlier of (i) November 3, 2024 or (ii) the 90th day after the repayment in full, and termination and discharge of all obligations (other than contingent indemnity obligations) under the MidCap Credit Facility. Interest on the Mann Group non-convertible note will be payable in kind by adding the amount thereof to the principal amount; provided that MannKind may, at its option, elect to pay any such interest on any interest payment date, if certain conditions are met, in shares of MannKind’s common stock at a price per shall equal to the last reported sale price on the trading day immediately prior to the interest payment date.
The Mann Group L L C | Privately Negotiated Exchange Agreement
Debt Instrument [Line Items]
Repayments of debt	$ 3
Common stock, shares issued | shares	7,142,857
Conversion price of shares | $ / shares	$ 1.12
Conversion of notes to common shares, value	$ 71.5
Accrued Paid-in-Kind Interest	$ 9.5
The Mann Group L L C | Privately Negotiated Exchange Agreement | Loan Arrangement
Debt Instrument [Line Items]
Common stock price per share | $ / shares	$ 2.50
The Mann Group L L C | Privately Negotiated Exchange Agreement | Loan Arrangement | Convertible Promissory Note
Debt Instrument [Line Items]
Principal amount	$ 35
The Mann Group L L C | Privately Negotiated Exchange Agreement | Loan Arrangement | Non-Convertible Note
Debt Instrument [Line Items]
Principal amount	$ 35.1

Borrowings - Schedule of Amorti

Borrowings - Schedule of Amortization of Premium and Accretion of Debt Issuance Costs (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Debt Disclosure [Abstract]
Amortization of debt discount	$ 89	$ 72
Accretion expense — debt issuance cost	$ (27)	(22)
Amortization of debt premium		$ (95)

Borrowings - Milestone Rights -

Borrowings - Milestone Rights - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Remaining milestone rights liability	$ 7,300	$ 7,300
Payment for milestone liability	5,000
Milestone Rights liability — current	1,337
Milestone rights liability	$ 5,926	$ 7,263

Schedule of Revenue from Collab

Schedule of Revenue from Collaborations and Services (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	$ 16,235	$ 17,448
Collaborations and services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	8,235	12,372
Collaborations and services | License Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	7,978	7,615
Collaborations and services | Research Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	158	4,658
Collaborations and services | Collaboration and License Agreement | Receptor CLA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	62	62
Collaborations and services | Distribution Agreement | Cipla Distribution Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total revenue from collaborations and services	$ 37	$ 37

Collaborations and Licensing _3

Collaborations and Licensing Arrangements - Additional Information (Detail) - USD ($)	Mar. 29, 2019	May 31, 2018	Mar. 31, 2020	Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Oct. 31, 2018	Sep. 30, 2018
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue — current			$ 30,840,000				$ 32,503,000
Revenue — collaborations and services			16,235,000		$ 17,448,000
Deferred revenue — long term			1,772,000				$ 8,344,000
AFREZZA product sales
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue — collaborations and services			8,000,000		$ 5,076,000
Collaboration and License Agreement | Receptor CLA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue — current			200,000
Collaboration and License Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received								$ 45,000,000
Milestone Payment Received	$ 12,500,000
Total transaction price			101,400,000
Deferred revenue			30,400,000
Collaboration and License Agreement | United Therapeutics Corporation | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments to be receive			25,000,000
Additional option exercise and development milestone payments to be receive			40,000,000
Research Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received									$ 10,000,000
Total transaction price			10,000,000
Deferred revenue — current			100,000
Research Agreement | United Therapeutics Corporation | Product Prototype
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total transaction price			$ 9,000,000
Revenue performance obligation, method used			The revenue for the product prototype is recognized using an output method (based on project milestones achieved and surveys of performance completed to date). The Company believes that this method best reflects the measure of progress toward complete satisfaction of the performance obligation.
Research Agreement | United Therapeutics Corporation | Engineering Consulting Services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total transaction price			$ 1,000,000
Revenue performance obligation, method used			The revenue for the engineering consulting services was recognized using a ratable method until the obligation was satisfied. The Company believes that this method best reflects the measure of progress toward complete satisfaction of the performance obligation.
Research Agreement | United Therapeutics Corporation | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments to be receive				$ 30,000,000
Supply and Distribution Agreement | AFREZZA product sales | Biomm
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue — collaborations and services				$ 700,000
License and Distribution Agreement | Foreign Country | India Tax Authority
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Income Taxes Paid						$ 200,000
License and Distribution Agreement | Cipla Distribution Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 1,900,000
Deferred revenue — current			100,000
Marketing and distribution agreement date		2018-05
Deferred revenue — long term			$ 1,800

Collaborations and Licensing _4

Collaborations and Licensing Arrangements - Additional Information (Detail 1) - USD ($) $ in Millions	Mar. 31, 2020	May 31, 2018	Dec. 31, 2016
Collaboration and License Agreement | Receptor CLA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2017-01-01
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue recognition period			4 years
Deferred revenue - nonrefundable license fee			$ 1
Collaboration and License Agreement | Receptor CLA | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-10-01
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue recognition period	39 months
License and Distribution Agreement | Cipla Distribution Agreement | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2018-06-01
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue recognition period		15 years
Deferred revenue - nonrefundable license fee		$ 2.2

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Fair Value Of Financial Instruments [Line Items]
Cash and cash equivalents	$ 38,868,000	$ 29,906,000
Restricted cash	316,000	316,000
Short-term investments	$ 0	19,978,000
Fair value of note payable to related party, description	The fair value measurement of debt instruments is based on a discounted cash flow model and is sensitive to the change in yield (Level 3 in the fair value hierarchy
Money Market Funds
Fair Value Of Financial Instruments [Line Items]
Cash and cash equivalents	$ 38,900,000	29,900,000
Restricted cash	$ 300,000	$ 300,000

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Fair Value Measurement of Debt Instruments Based on Discounted Cash Flow Model and Sensitive to Change in Yield (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Mann Group Promissory Notes | Note Payable Yield Changes 1
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	2.00%
Note payable, percentage of hypothetical yield	37
Note payable to related party, fair value	$ 38
Note payable to related party, fair value after change	36.4
Change in fair value of note payable value due to change in interest rate percentage	$ (1.6)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(4.20%)
Mann Group Promissory Notes | Note Payable Yield Changes 2
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	(2.00%)
Note payable, percentage of hypothetical yield	33
Note payable to related party, fair value	$ 38
Note payable to related party, fair value after change	39.8
Change in fair value of note payable value due to change in interest rate percentage	$ 1.8
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	4.70%
Mann Group Promissory Notes | Note Payable Yield Changes 3
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	4.00%
Note payable, percentage of hypothetical yield	39
Note payable to related party, fair value	$ 38
Note payable to related party, fair value after change	34.8
Change in fair value of note payable value due to change in interest rate percentage	$ (3.2)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(8.40%)
Mann Group Promissory Notes | Note Payable Yield Changes 4
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	(4.00%)
Note payable, percentage of hypothetical yield	31
Note payable to related party, fair value	$ 38
Note payable to related party, fair value after change	41.8
Change in fair value of note payable value due to change in interest rate percentage	$ 3.8
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	10.00%
Senior Notes | Note Payable Yield Changes 1
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	2.00%
Note payable, percentage of hypothetical yield	37
Note payable to related party, fair value	$ 7.6
Note payable to related party, fair value after change	7.5
Change in fair value of note payable value due to change in interest rate percentage	$ (0.1)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(1.30%)
Senior Notes | Note Payable Yield Changes 2
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	(2.00%)
Note payable, percentage of hypothetical yield	33
Note payable to related party, fair value	$ 7.6
Note payable to related party, fair value after change	7.8
Change in fair value of note payable value due to change in interest rate percentage	$ 0.2
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	2.60%
Senior Notes | Note Payable Yield Changes 3
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	4.00%
Note payable, percentage of hypothetical yield	39
Note payable to related party, fair value	$ 7.6
Note payable to related party, fair value after change	7.4
Change in fair value of note payable value due to change in interest rate percentage	$ (0.2)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(2.60%)
Senior Notes | Note Payable Yield Changes 4
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	35
Note payable, percentage of interest rate increases (decreases)	(4.00%)
Note payable, percentage of hypothetical yield	31
Note payable to related party, fair value	$ 7.6
Note payable to related party, fair value after change	7.9
Change in fair value of note payable value due to change in interest rate percentage	$ 0.3
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	3.90%
MidCap Credit Facility | Note Payable Yield Changes 1
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	17
Note payable, percentage of interest rate increases (decreases)	1.00%
Note payable, percentage of hypothetical yield	18
Note payable to related party, fair value	$ 35.8
Note payable to related party, fair value after change	35.1
Change in fair value of note payable value due to change in interest rate percentage	$ (0.7)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(2.00%)
MidCap Credit Facility | Note Payable Yield Changes 2
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	17
Note payable, percentage of interest rate increases (decreases)	(1.00%)
Note payable, percentage of hypothetical yield	16
Note payable to related party, fair value	$ 35.8
Note payable to related party, fair value after change	36.6
Change in fair value of note payable value due to change in interest rate percentage	$ 0.8
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	2.20%
MidCap Credit Facility | Note Payable Yield Changes 3
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	17
Note payable, percentage of interest rate increases (decreases)	2.00%
Note payable, percentage of hypothetical yield	19
Note payable to related party, fair value	$ 35.8
Note payable to related party, fair value after change	34.3
Change in fair value of note payable value due to change in interest rate percentage	$ (1.5)
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	(4.20%)
MidCap Credit Facility | Note Payable Yield Changes 4
Fair Value Of Financial Instruments [Line Items]
Note payable, percentage of yield	17
Note payable, percentage of interest rate increases (decreases)	(2.00%)
Note payable, percentage of hypothetical yield	15
Note payable to related party, fair value	$ 35.8
Note payable to related party, fair value after change	37.4
Change in fair value of note payable value due to change in interest rate percentage	$ 1.6
Increase (decrease) in fair value of note payable percentage due to increases (decreases) in interest rate percentage	4.50%

Fair Value of Financial Instr_5

Fair Value of Financial Instruments - Fair Value of Financial Instruments (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financial liabilities:
Financial liabilities fair value	$ 95.7	$ 110.6
MidCap Credit Facility
Financial liabilities:
Financial liabilities fair value	35.8	40
2024 Convertible Notes
Financial liabilities:
Financial liabilities fair value	3.1	3.7
June 2020 Note
Financial liabilities:
Financial liabilities fair value	2.4	2.3
December 2020 Note
Financial liabilities:
Financial liabilities fair value	2.1	2
Mann Group Promissory Notes
Financial liabilities:
Financial liabilities fair value	38	46.2
Milestone Rights Liability
Financial liabilities:
Financial liabilities fair value	14.3	16.4
Carrying Value
Financial liabilities:
Financial liabilities fair value	126.3	126.2
Carrying Value | MidCap Credit Facility
Financial liabilities:
Financial liabilities fair value	38.9	38.9
Carrying Value | 2024 Convertible Notes
Financial liabilities:
Financial liabilities fair value	5	5
Carrying Value | June 2020 Note
Financial liabilities:
Financial liabilities fair value	2.6	2.5
Carrying Value | December 2020 Note
Financial liabilities:
Financial liabilities fair value	2.5	2.5
Carrying Value | Mann Group Promissory Notes
Financial liabilities:
Financial liabilities fair value	70	70
Carrying Value | Milestone Rights Liability
Financial liabilities:
Financial liabilities fair value	7.3	7.3
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	95.7	110.6
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 3 | MidCap Credit Facility
Financial liabilities:
Financial liabilities fair value	35.8	40
Estimate of Fair Value Measurement | 2024 Convertible Notes | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	3.1	3.7
Estimate of Fair Value Measurement | June 2020 Note | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	2.4	2.3
Estimate of Fair Value Measurement | December 2020 Note | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	2.1	2
Estimate of Fair Value Measurement | Mann Group Promissory Notes | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	38	46.2
Estimate of Fair Value Measurement | Milestone Rights Liability | Fair Value, Inputs, Level 3
Financial liabilities:
Financial liabilities fair value	$ 14.3	$ 16.4

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Based Compensation Expense Recognized in Accompanying Condensed Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock compensation expense	$ 1,128	$ 999
Restricted Stock Units and Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock compensation expense	1,066	883
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock compensation expense	$ 62	$ 116

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Feb. 29, 2020	Mar. 31, 2020	Mar. 31, 2019
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-option		$ 0.5
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years	4 years
Aggregate number of shares granted to awards, share-based compensation arrangements		78,500	294,900
Weighted average exercise price of the stock options granted		$ 1.25	$ 1.49
Weighted average grant date fair value of the stock options granted		$ 0.93	$ 1.06
Risk-free interest rate		0.79%
Expected life		5 years 8 months 1 day
Volatility rate		93.83%
Dividend yield		0.00%
Fair value of stock granted, share-based compensation arrangements			$ 0.3
Options and Performance-based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to options		$ 8
Employees | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted		230,000
Restricted stock units weighted average grant date fair value		$ 1.25	$ 1.49
Vesting period		4 years
Number of restricted stock units issued			754,729
Vesting rights percentage	100.00%
Non-employee Directors | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted		42,067
Restricted stock units weighted average grant date fair value		$ 1.17

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended				3 Months Ended			12 Months Ended
	Aug. 31, 2019$ / sharesshares	Dec. 31, 2018$ / sharesshares	Nov. 30, 2017USD ($)	May 31, 2017USD ($)	Mar. 31, 2020USD ($)shares	Mar. 31, 2019USD ($)	Jun. 30, 2018USD ($)Vehicle	Dec. 31, 2019USD ($)Vehicle	Jan. 01, 2019USD ($)	Jul. 01, 2013USD ($)
Commitments And Contingencies [Line Items]
Purchase obligation extended term	2026
Supply Agreement expiration period					Dec. 31, 2026
Supply Agreement renewal period					2 years
Operating lease, non-current liabilities					$ 2,155,000			$ 2,514,000
Operating lease costs					400,000	$ 500,000
Operating lease, cash paid					400,000	500,000
Variable lease costs					$ 100,000	$ 100,000
Operating lease, weighted average discount rate					7.50%	7.20%
Operating lease, weighted-average remaining lease term					2 years 8 months 12 days	3 years 9 months 18 days
Underwriting Agreement with Leerink Partners LLC
Commitments And Contingencies [Line Items]
Stock purchase agreements date		Dec. 31, 2018
Warrants exercisable | shares					7,250,000
Warrant expiration date					Jun. 26, 2020
Underwriting Agreement with Leerink Partners LLC | Warrants
Commitments And Contingencies [Line Items]
Exercise price of warrants | $ / shares		$ 1.60
Lease Agreement with Enterprise | Vehicle Leases
Commitments And Contingencies [Line Items]
Number of vehicle leases | Vehicle							119	90
Operating lease rent expenses							$ 83,000	$ 65,000
Number of vehicle leases removed | Vehicle								29
Lease expiration period							48 months
Operating lease right-of-use assets									$ 1,600,000
Operating lease liabilities									1,900,000
Operating lease, non-current other assets					$ 1,600,000
Operating lease, other current liabilities					600,000
Operating lease, non-current liabilities					1,300,000
Maximum | Underwriting Agreement with Leerink Partners LLC | Warrants
Commitments And Contingencies [Line Items]
Warrants to purchase common stock | shares		26,666,667
MidCap Credit Facility
Commitments And Contingencies [Line Items]
Warrants to purchase common stock | shares	1,171,614
Exercise price of warrants | $ / shares	$ 1.11
Deerfield | Milestone Rights Liability
Commitments And Contingencies [Line Items]
Contingent liability remain payable					70,000,000
Deerfield | Milestone Rights Liability | Maximum
Commitments And Contingencies [Line Items]
Contingent liability for milestone payments										$ 90,000,000
Russell Ranch Road II LLC | Office Lease
Commitments And Contingencies [Line Items]
Operating lease rent expenses			$ 35,969	$ 40,951
Operating lease right-of-use assets									3,200,000
Operating lease liabilities									$ 3,500,000
Operating lease, other current liabilities					900,000
Operating lease, non-current liabilities					$ 2,600,000
Percentage of annual increase in lease payment			3.00%	3.00%
Lease expiration date			Jan. 31, 2023	Jan. 31, 2023
Lease renewal option			5 years	5 years
Reimbursement amount received for tenant improvements			$ 56,325

Commitments and Contingencies_2

Commitments and Contingencies - Annual Purchase Requirements under Amended Contract (Detail) € in Millions	Mar. 31, 2020EUR (€)
Purchase Obligation Fiscal Year Maturity [Abstract]
2020	€ 6.6
2021	6.6
2022	8.5
2023	10.8
2024	14.6
2025	15.5
2026	€ 19.4

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Future Minimum Office And Vehicle Lease Payments (Detail) - office and vehicle - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Commitments And Contingencies [Line Items]
2020	$ 1,105
2020		$ 1,470
2021	1,500	1,500
2022	1,241	1,241
2023	88	88
Total	$ 3,934	$ 4,299

Subsequent Event - Additional I

Subsequent Event - Additional Information (Detail) - Subsequent Event	Apr. 10, 2020USD ($)
US Small Business Administration
Subsequent Event [Line Items]
Maximum payroll cost exclude compensation of individual employee	$ 100,000
Forgiveness reduction in case of reduction in salaries and wages of employees with	$ 100,000
Minimum | US Small Business Administration
Subsequent Event [Line Items]
Debt instrument number of days loan can be forgiven from beginning	60 days
Maximum | US Small Business Administration
Subsequent Event [Line Items]
Debt instrument number of days loan can be forgiven from beginning	120 days
Percentage of non payroll costs	25.00%
Percentage of decrease in salaries and wages for employees	25.00%
Paycheck Protection Program Loan
Subsequent Event [Line Items]
Proceeds from loans	$ 4,900,000
Maturity date	Apr. 9, 2022
Annual interest rate	0.98%
Debt instrument, commencement of payment date	Nov. 9, 2020
Debt instrument, payment terms	Commencing November 9, 2020, the Company is required to pay the lender equal monthly payments of principal and interest as required to fully amortize by April 9, 2022 the principal amount outstanding on the PPP Loan as of October 9, 2020.
Debt instrument, frequency of periodic payment	equal monthly payments
Debt instrument, prepayment penalties	$ 0