Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Previously Reported [Member]	Redeemable Convertible Preferred Stock [Member]	Redeemable Convertible Preferred Stock [Member] Previously Reported [Member]	Redeemable Convertible Preferred Stock [Member] Recapitalization [Member]	Common Stock [Member]	Common Stock [Member] Previously Reported [Member]	Common Stock [Member] Recapitalization [Member]	Additional Paid In Capital [Member]	Additional Paid In Capital [Member] Previously Reported [Member]	Additional Paid In Capital [Member] Recapitalization [Member]	Accumulated Deficit [Member]	Accumulated Deficit [Member] Previously Reported [Member]
Beginning Balance at Mar. 31, 2020	$ (620,883)	$ (620,883)	$ 755,083	$ 755,083		$ 9	$ 0	$ 9	$ 172,727	$ 172,736	$ (9)	$ (793,619)	$ (793,619)
Beginning Balance, Shares at Mar. 31, 2020			198,274,933	86,443,341	111,831,592	101,652,799	44,318,298	57,334,501
Issuance of common stock upon exercise of stock options	1,139								1,139
Issuance of common stock upon exercise of stock options, shares						676,618
Vesting Early Exercised Stock Options	4,241								4,241
Stock-based compensation expense	11,454								11,454
Net Loss	(35,770)											(35,770)
Ending Balance at Jun. 30, 2020	(639,819)		$ 755,083			$ 9			189,561			(829,389)
Ending Balance, Shares at Jun. 30, 2020			198,274,933			102,329,417
Beginning Balance at Mar. 31, 2021	(595,619)	$ (595,619)	$ 837,351	$ 837,351		$ 12	$ 0	$ 12	381,607	$ 381,619	$ (12)	(977,238)	$ (977,238)
Beginning Balance, Shares at Mar. 31, 2021			209,181,855	91,198,378	117,983,477	124,529,784	54,292,140	70,237,644
Preferred stock conversion	837,351		$ (837,351)			$ 21			837,330
Preferred stock conversion, shares			(209,181,855)			(209,181,855)
Issuance of common stock upon Merger, net of transaction costs and Merger warrant liability	200,579					$ 5			200,574
Issuance Of Common Stock Upon Merger And Merger Warrant Liability Shares						46,901,747
Issuance of PIPE shares	250,000					$ 3			249,997
Issuance of PIPE shares, shares						25,000,000
Issuance of common stock upon exercise of stock options	$ 2,553								2,553
Issuance of common stock upon exercise of stock options, shares	0					818,479
Vesting Early Exercised Stock Options	$ 0
Stock-based compensation expense	9,704								9,704
Net Loss	(42,026)
Ending Balance at Jun. 30, 2021	$ 662,542		$ 0			$ 41			$ 1,681,765			$ (1,019,264)
Ending Balance, Shares at Jun. 30, 2021			0			406,431,865