Consolidated Statements of Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Accumulated Other Comprehensive (Income) Loss	Accumulated Deficit	Private Placement Cowen and Company, LLC	Private Placement Cowen and Company, LLC Common Shares	Private Placement Cowen and Company, LLC Additional Paid-in Capital	Private Placement Roivant Sciences, Ltd.	Private Placement Roivant Sciences, Ltd. Common Shares	Private Placement Roivant Sciences, Ltd. Additional Paid-in Capital	Private Placement NovaQuest	Private Placement NovaQuest Common Shares	Private Placement NovaQuest Additional Paid-in Capital	Public Offering	Public Offering Common Shares	Public Offering Additional Paid-in Capital
Beginning balance (in shares) at Mar. 31, 2018		60,997,856
Beginning balance at Mar. 31, 2018	$ 37,729	$ 1	$ 266,178	$ 24	$ (228,474)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)							3,970,129			1,110,015			2,286,284			3,533,399
Shares issued						$ 84,052		$ 84,052	$ 22,500		$ 22,500	$ 37,982		$ 37,982	$ 74,391		$ 74,391
Share-based compensation expense	18,067		18,067
Capital contribution from former majority shareholder — share-based compensation	629		629
Capital contribution from former majority shareholder	752		752
Foreign currency translation adjustment	483			483
Issuance of shares upon exercise of stock options and vesting of PSUs and RSUs (in shares)		159,807
Issuance of shares upon exercise of stock options and vesting of PSUs and RSUs	1,300		1,300
Net loss	(273,551)				(273,551)
Ending balance (in shares) at Mar. 31, 2019		72,057,490
Ending balance at Mar. 31, 2019	4,334	$ 1	505,851	507	(502,025)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)							106,494									17,424,243
Shares issued		$ 1				$ 2,546		$ 2,546							$ 134,458		$ 134,457
Share-based compensation expense	40,102		40,102
Capital contribution from former majority shareholder — share-based compensation	149		149
Capital contribution from former majority shareholder	334		334
Foreign currency translation adjustment	(2,153)			(2,153)
Issuance of shares upon exercise of stock options and vesting of PSUs and RSUs (in shares)		245,771
Issuance of shares upon exercise of stock options and vesting of PSUs and RSUs	942		942
Net loss	$ (288,989)				(288,989)
Ending balance (in shares) at Mar. 31, 2020	89,833,998	89,833,998
Ending balance at Mar. 31, 2020	$ (108,277)	$ 2	684,381	(1,646)	(791,014)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	53,676		53,676
Share-based compensation awards reclassified to current liabilities	(17,473)		(17,473)
Share-based compensation liabilities reclassified to equity upon settlement of awards	6,446		6,446
Share-based compensation expense reclassified to current liabilities	$ (10,609)		(10,609)
Issuance of shares upon exercise of stock options (in shares)	905,776	905,776
Issuance of shares upon exercise of stock options	$ 6,709		6,709
Vesting of share awards, net of shares witheld for taxes (in shares)		261,095
Vesting of share awards, net of shares withheld for taxes	(13,664)		(13,664)
Foreign currency translation adjustment	(15,639)			(15,639)
Net loss	$ (255,134)				(255,134)
Ending balance (in shares) at Mar. 31, 2021	91,000,869	91,000,869
Ending balance at Mar. 31, 2021	$ (353,965)	$ 2	$ 709,466	$ (17,285)	$ (1,046,148)