Stockholders' Equity and Stock-based Compensation (Details) - USD ($)	1 Months Ended		3 Months Ended
	Jan. 31, 2018	Oct. 31, 2017	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Proceeds from issuance of shares under the agreement			$ 12,315,000	$ 2,248,000
Issuance of common shares pursuant to the agreement			$ 12,315,000	$ 2,248,000
Preferred Shares
Class of Stock [Line Items]
Shares issued (in shares)		1,164,000
Roivant Sciences Ltd
Class of Stock [Line Items]
Ownership percentage by noncontrolling owners after conversion		42.00%
Maximum ownership percentage by noncontrolling owners		49.99%
Proceeds from sale of stock	$ 66,400,000	$ 50,000,000
Roivant Sciences Ltd | Convertible Preferred Stock
Class of Stock [Line Items]
Issuance of common shares pursuant to the agreement		$ 116,400,000
Preferred stock dividend rate as a percent		8.75%	8.75%
Preferred stated value (in dollars per share)		$ 7.13
Number of common shares to be issued upon conversion of convertible preferred stock		0
Investment commitment period		4 years
Open Market Sale Agreement | Jefferies LLC | Common Shares
Class of Stock [Line Items]
Aggregate sale price of common shares under agreement			$ 42,729,812		$ 50,000,000.0	$ 50,000,000.0
Number of shares issued under agreement (in sales)			4,147,081	614,401
Proceeds from issuance of shares under the agreement			$ 12,300,000	$ 2,700,000
Sale Agreement | Open Market Sale Agreement | Jefferies LLC | Common Shares
Class of Stock [Line Items]
Proceeds from issuance of shares under the agreement			5,500,000
Share issuance costs			600,000
Amended Sale Agreement | Open Market Sale Agreement | Jefferies LLC | Common Shares
Class of Stock [Line Items]
Proceeds from issuance of shares under the agreement			$ 6,800,000.0