Collaboration, Licensing and Other Arrangements - Additional Information (Detail) - USD ($)			1 Months Ended	3 Months Ended		12 Months Ended	20 Months Ended
		Oct. 31, 2021	May 31, 2018	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Nov. 30, 2020	Oct. 31, 2018
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue - current				$ 1,307,000		$ 827,000
Deferred revenue - non-current				26,116,000		19,543,000
Revenue' collaborations and services				11,992,000	$ 17,436,000
Collaborations and services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue' collaborations and services				2,166,000	9,337,000
Commercial product sales
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue' collaborations and services				9,826,000	8,099,000
Collaboration and License Agreement | United Therapeutics Corporation
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received								$ 45,000,000.0
Milestone Payment Received							$ 12,500,000
Total anticipated cash flow	[1]	$ 463,500,000
Deferred revenue				25,700,000
Deferred revenue - current				1,100,000
Deferred revenue - non-current				24,600,000
Collaboration and License Agreement | United Therapeutics Corporation | Manufacturing Services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Allocated transaction price		144,500,000
Collaboration and License Agreement | United Therapeutics Corporation | Manufacturing Services | Transaction Price For The Contractual Obligations
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total anticipated cash flow		64,300,000
Collaboration and License Agreement | United Therapeutics Corporation | Next-Gen R&D Services | Transaction Price For The Performance Obligations
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Total anticipated cash flow		$ 399,200,000
Collaboration and License Agreement | United Therapeutics Corporation | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional option exercise and development milestone payments to be receive				$ 40,000,000.0
Commercial Supply Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Amendment description				As amended in October 2021, the term of the CSA continues until December 31, 2031 (unless earlier terminated) and is thereafter renewed automatically for additional, successive two-year terms unless (i) United Therapeutics provides notice to the Company at least 24 months in advance of such renewal that United Therapeutics does not wish to renew the CSA or (ii) the Company provides notice to United Therapeutics at least 48 months in advance of such renewal that the Company does not wish to renew the CSA.
Commercial Supply Agreement | United Therapeutics Corporation | Collaborations and services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue' collaborations and services	[2]			$ 694,000
Co-Promotion Agreement | Collaborations and services
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Reserve for allowance for credit losses				800,000
Supply and Distribution Agreement | Commercial product sales | Biomm
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue' collaborations and services				0		$ 0
License and Distribution Agreement | Cipla Ltd
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue				1,600,000
Deferred revenue - current				100,000
Deferred revenue - non-current				1,500,000
Marketing and distribution agreement date			2018-05
License and Distribution Agreement | Collaborations and services | Cipla Ltd
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue' collaborations and services				$ 37,000	$ 36,000

[1] The total anticipated cash flow includes a transaction price of $64.3 million for the contractual obligations under the CSA for the Manufacturing Services and the Next-Gen R&D Services performance obligations and $399.2 million for future supply of Tyvaso DPI over the remaining term of the CSA.

[2] Amount consists of revenue recognized for Manufacturing Services for the three months ended March 31, 2022