Collaboration and Licensing Arrangements - Additional Information (Detail)		1 Months Ended	3 Months Ended								12 Months Ended
	Dec. 30, 2016 USD ($)	May 31, 2018	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Milestone	Oct. 16, 2018 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Net revenue - commercial product sales			$ 16,031,000	$ 4,469,000	$ 3,893,000	$ 3,465,000	$ 4,530,000	$ 2,043,000	$ 2,163,000	$ 3,009,000	$ 27,859,000	$ 11,745,000	$ 174,758,000
Deferred payments from collaborations - current			36,885,000				250,000				36,885,000	250,000
Deferred payments from collaborations - long term			10,680,000				$ 500,000				10,680,000	500,000
Income Taxes Paid											240,000	51,000
Sanofi-Aventis Deutschland GmbH | Put Option
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment for insulin put option										$ 30,600,000
AFREZZA product sales
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Net revenue - commercial product sales											17,276,000	$ 9,192,000	1,895,000
Collaboration and License Agreement | Sanofi-Aventis Deutschland GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognition upfront payment													$ 150,000,000
Number of milestone | Milestone													2
Collaboration and License Agreement | Sanofi-Aventis Deutschland GmbH | Operating loss Sharing
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue offset in collaboration agreement													$ 64,900,000
Collaboration and License Agreement | Receptor
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred payments from collaboration			500,000								500,000
Deferred payments from collaborations - current			300,000								300,000
Nonrefundable option exercise and license fee	$ 1,000,000
Collaboration and License Agreement | Milestone Payment One | Sanofi-Aventis Deutschland GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognition milestone payment													25,000,000
Collaboration and License Agreement | Milestone Payment Two | Sanofi-Aventis Deutschland GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognition milestone payment													25,000,000
Collaboration and License Agreement | AFREZZA product sales | Sanofi-Aventis Deutschland GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue offset in collaboration agreement													17,500,000
Collaboration and License Agreement | Insulin Put | Sanofi-Aventis Deutschland GmbH
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue offset in collaboration agreement													$ 19,400,000
Collaboration and License Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received														$ 45,000,000
Net revenue - commercial product sales											6,400,000
Deferred payments from collaboration			38,600,000								38,600,000
Deferred payments from collaborations - current			30,500,000								30,500,000
Deferred payments from collaborations - long term			8,100,000								8,100,000
Total transaction price			97,500,000								97,500,000
Collaboration and License Agreement | United Therapeutics Corporation | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments to be receive			50,000,000								50,000,000
Additional option exercise and development milestone payments to be receive			40,000,000								40,000,000
Research Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received				10,000,000
Net revenue - commercial product sales											3,800,000
Deferred payments from collaboration			10,000,000								10,000,000
Deferred payments from collaborations - current			6,000,000								6,000,000
Deferred payments from collaborations - long term			200,000								200,000
Total transaction price			10,000,000								10,000,000
Research Agreement | United Therapeutics Corporation | Product Prototype
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total transaction price			9,000,000								$ 9,000,000
Revenue performance obligation, method used											The revenue for the product prototype is recognized using a proportional performance method (based on an estimated percentage of the Company’s efforts required in relation toward overall satisfaction of the obligation). 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								$ 1,000,000
Revenue performance obligation, method used											The revenue for the engineering consulting services is recognized using a ratable method until the obligation is satisfied and 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]
Additional milestone payments to be received				$ 30,000,000
Distribution Agreement | Foreign Country | India Tax Authority
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Income Taxes Paid											$ 200,000
Distribution Agreement | Cipla Ltd
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred payments from collaboration			2,100,000								2,100,000
Deferred payments from collaborations - current			$ 100,000								$ 100,000
Marketing and distribution agreement date		2018-05