Borrowings - MidCap Credit Facility - Additional Information (Detail)			1 Months Ended						3 Months Ended	6 Months Ended	12 Months Ended
		Apr. 22, 2021 USD ($) Installment	Apr. 30, 2021 USD ($)	Dec. 31, 2020 USD ($) Installment $ / shares shares	Nov. 30, 2020 USD ($) Installment $ / shares	Aug. 31, 2020 USD ($)	Dec. 31, 2019	Aug. 31, 2019 USD ($) Installment $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2021 USD ($)
Debt Instrument [Line Items]
Loss on extinguishment of debt									$ 22,130,000	$ 22,130,000
Unamortized debt discount									1,386,000	$ 1,386,000
MidCap Credit Facility
Debt Instrument [Line Items]
Prepaid of borrowing			$ 10,000,000.0
Minimum cash covenant					$ 30,000,000.0			$ 10,000,000.0
Debt payable number of equal monthly installments | Installment					24
Debt instrument payment term description										Principal on each term loan advance under Tranche 1, Tranche 2 and, if applicable, Tranche 3 is payable in 24 equal monthly installments beginning September 1, 2023, until paid in full on August 1, 2025.
Debt instrument minimum unrestricted cash and short-term investments								$ 90,000,000.0
Principal prepayment against outstanding term loans		$ 10,000,000.0
Original exit fee and prepayment penalties		1,000,000.0	$ 1,000,000.0
Unamortized debt discount									400,000	$ 400,000
Debt Instrument unamortized prepayment penalty.									$ 900,000	$ 900,000
Interest on loans increased, percentage								2.00%
Term loan advance percentage of amount drawdown								3.25%
Exercise price of warrants | $ / shares					$ 2.91			$ 1.11
MidCap Credit Facility | On or After April 23, 2022 Through and Including April 22, 2023
Debt Instrument [Line Items]
Early termination fees, percentage										2.00%
MidCap Credit Facility | On or Prior to April 22, 2022
Debt Instrument [Line Items]
Early termination fees, percentage										3.00%
MidCap Credit Facility | On or After April 23, 2023 Through Maturity Date
Debt Instrument [Line Items]
Early termination fees, percentage										1.00%
MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate floor	[1]									1.00%
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%
Tranche 1 | MidCap Credit Facility
Debt Instrument [Line Items]
Advance of borrowing						$ 40,000,000.0		$ 40,000,000.0
Minimum cash covenant						$ 40,000,000.0
Debt payable number of equal monthly installments | Installment								24
Loss on extinguishment of debt											$ 200,000
Maturity date								Aug. 01, 2025
Annual interest rate								8.25%
Line of credit facility principal payment start date								Sep. 01, 2023
Warrants to purchase of common stock | shares								1,171,614
Exercise price of warrants | $ / shares								$ 1.11
Tranche 1 | MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)								6.25%
Interest rate floor								1.00%
Tranche 2 | MidCap Credit Facility
Debt Instrument [Line Items]
Advance of borrowing											10,000,000.0
Amount available under credit facility				$ 10,000,000.0							$ 10,000,000.0
Debt payable number of equal monthly installments | Installment				24
Debt discount and a de minimis amount of debt issuance costs										$ 300,000
Maturity date				Aug. 01, 2025
Annual interest rate				8.25%							8.25%
Line of credit facility principal payment start date				Sep. 01, 2023
Warrants to purchase of common stock | shares				111,853							111,853
Exercise price of warrants | $ / shares				$ 2.91							$ 2.91
Tranche 2 | MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)				6.25%
Interest rate floor				1.00%
Tranche 3 | MidCap Credit Facility
Debt Instrument [Line Items]
Amount available under credit facility		$ 60,000,000.0						$ 60,000,000.0				$ 25,000,000.0
Debt payable number of equal monthly installments | Installment		24
Debt instrument advance available date		Jun. 30, 2022
Debt instrument extended interest-only date		Sep. 01, 2023
Maturity date		Aug. 01, 2025
Debt instrument payment term description		On April 22, 2021, the Company entered into the seventh amendment of the MidCap credit facility, pursuant to which the parties agreed to, among other things, (i) increase the amount available under the third advance from $25.0 million to $60.0 million and extend the date through which the third advance is available to June 30, 2022, (ii) amend the conditions to the third advance of $60.0 million being available to draw, including certain milestone conditions associated with Tyvaso DPI, (iii) remove the Company’s obligation to issue a warrant to purchase shares of the Company’s common stock upon drawing down the third advance, (iv) extend the interest-only period until September 1, 2023 and extend the maturity date until August 1, 2025, (v) amend the financial covenant relating to trailing 12 month minimum Afrezza net revenue, (vi) decrease the minimum cash covenant, (vii) decrease the interest rate on any amounts outstanding, now or in the future, under the MidCap credit facility, (viii) permit the Company to make certain acquisitions, subject to requirements, and (ix) permit the Company to make investments of up to an additional $9.0 million so long as the Company has $90.0 million or more of unrestricted cash and short-term investments following such investment.
Maximum value of additional investment limit		$ 9,000,000.0
Debt instrument minimum unrestricted cash and short-term investments		$ 90,000,000.0
Annual interest rate		8.25%
Line of credit facility principal payment start date		Sep. 01, 2023
Tranche 3 | MidCap Credit Facility | LIBOR
Debt Instrument [Line Items]
Interest rate (LIBOR)		6.25%
Interest rate floor		1.00%

[1] In April 2021, the Company prepaid $10.0 million principal balance and amended the MidCap credit facility. The interest rate prior to the amendment was one-month LIBOR (2% floor) plus 6.75% and the maturity date was in August 2024.