Investments and Fair Value Instruments - Summary of Changes in Fair Value and Other Adjustments of Liabilities (Detail) - Level 3 [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 5,463
Ending Balance	2,039
Common Stock Warrant Liability [Member] | Purchase Agreement [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	7
Common Stock Warrant Liability [Member] | June 2019 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	170
Common Stock Warrant Liability [Member] | September 2019 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	223
Common Stock Warrant Liability [Member] | January 2021 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	2,993
Contingent Liabilities [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	2,070
Change in fair value of contingent consideration	(31)
Ending Balance	2,039
ASU 2020-06 [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Change in fair value of contingent consideration	(31)
ASU 2020-06 [Member] | Reclassification upon Adoption [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(3,392)
ASU 2020-06 [Member] | Reclassification upon Adoption [Member] | Common Stock Warrant Liability [Member] | Purchase Agreement [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(7)
ASU 2020-06 [Member] | Reclassification upon Adoption [Member] | Common Stock Warrant Liability [Member] | June 2019 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(170)
ASU 2020-06 [Member] | Reclassification upon Adoption [Member] | Common Stock Warrant Liability [Member] | September 2019 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	(223)
ASU 2020-06 [Member] | Reclassification upon Adoption [Member] | Common Stock Warrant Liability [Member] | January 2021 Offering [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ (2,993)