Debt Instrument, Business Day Notice Period for Prepayment

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- Definition

Debt Instrument, Covenant, Repayment Period Upon Change in Control

+ References

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- Definition

Debt Instrument, Default Interest Rate

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- Definition

Related Party, Ownership Interest Held By Related Party

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- Definition

Related Party, Ownership Interest Held By Related Party, Shares

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- Definition

Related Party Transaction, Agreement Extension Term

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- Definition

Related Party Transaction, Agreement Term

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- Definition

Related Party Transaction, Number of Independent Directors Required for Audit Committee

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- Definition

Related Party Transaction, Ownership Threshold for Appointment of Directors

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- Definition

Related Party Transaction, Ownership Threshold for Right of Ownership Percentage Maintenance

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- Definition

Related Party Transaction, Ownership Threshold for Voting Rights

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- Definition

Related Party Transaction, Termination Notice Period

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- Definition

Costs of sales and operating expenses for the period incurred from transactions with related parties.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties.

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- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Cash received on stock transaction after deduction of issuance costs.

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No definition available.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Related Party Transactions (Narrative) (Details)						1 Months Ended	12 Months Ended
Related Party Transactions (Narrative) (Details)	Aug. 05, 2020 USD ($)	Aug. 01, 2020	Dec. 30, 2019 USD ($)	Dec. 27, 2019 USD ($) director day shares	Jun. 04, 2019 USD ($) $ / shares shares	Apr. 30, 2018 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Proceeds from related party debt financing							$ 245,000,000	$ 113,700,000	$ 0
Amounts due to related parties							543,000	15,000
Majority Shareholder
Related Party Transaction [Line Items]
Amounts due to related party (less than)							$ 100,000
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder
Related Party Transaction [Line Items]
Number of shares owned (in shares) \| shares				45,008,604			48,641,181
Ownership percentage				50.20%			53.50%
Ownership threshold for appointment of directors				50.00%
Number of independent directors required for audit committee \| director				3
Ownership threshold for voting rights				60.00%
Ownership threshold for right of ownership percentage maintenance				50.00%
Amounts due to related parties							$ 100,000
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder \| Sumitovant Consulting Agreement
Related Party Transaction [Line Items]
Expenses incurred under agreements							800,000
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder \| Sumitovant Other Expenses Agreement
Related Party Transaction [Line Items]
Expenses incurred under agreements							700,000
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder \| Sunovion Pharmaceuticals Inc. Market Access Services Agreement
Related Party Transaction [Line Items]
Expenses incurred under agreements							3,800,000
Amounts due to related parties							400,000
Agreement term		3 years
Agreement extension term		1 year
Termination notice period		9 months
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder \| Sunovion Pharmaceuticals Inc. Market Access Services Agreement \| SG&A expense
Related Party Transaction [Line Items]
Expenses incurred under agreements							3,700,000
Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder \| Sunovion Pharmaceuticals Inc. Market Access Services Agreement \| R&D expense
Related Party Transaction [Line Items]
Expenses incurred under agreements							100,000
Roivant Sciences, Ltd. \| Former Majority Shareholder \| Service Agreement
Related Party Transaction [Line Items]
Expenses incurred under agreements								600,000	4,800,000
Roivant Sciences, Ltd. \| Former Majority Shareholder \| Share-based Compensation, Expense Allocated to Company
Related Party Transaction [Line Items]
Expenses incurred under agreements							0	100,000	600,000
Private Placement \| Roivant Sciences, Ltd. \| Majority Shareholder
Related Party Transaction [Line Items]
Number of shares issued (in shares) \| shares						1,110,015
Price of shares (in USD per share) \| $ / shares						$ 20.27
Net proceeds from sale of shares						$ 22,500,000
Private Placement \| Roivant Sciences, Ltd. \| Former Majority Shareholder
Related Party Transaction [Line Items]
Number of shares issued (in shares) \| shares						1,110,015
Price of shares (in USD per share) \| $ / shares						$ 20.27
Net proceeds from sale of shares						$ 22,500,000
Public Offering
Related Party Transaction [Line Items]
Number of shares issued (in shares) \| shares					17,424,243
Price of shares (in USD per share) \| $ / shares					$ 8.25
Net proceeds from sale of shares					$ 134,500,000
Public Offering \| Roivant Sciences, Ltd. \| Former Majority Shareholder
Related Party Transaction [Line Items]
Number of shares issued (in shares) \| shares					2,424,242
Price of shares (in USD per share) \| $ / shares					$ 8.25
Net proceeds from sale of shares					$ 20,000,000.0
Term Loan \| Letter Agreement with Sumitomo Dainippon Pharma, Co., Ltd.
Related Party Transaction [Line Items]
Proceeds from related party debt financing			$ 113,700,000
Term Loan \| Letter Agreement with Sumitomo Dainippon Pharma, Co., Ltd. \| Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder
Related Party Transaction [Line Items]
Maximum borrowing commitment				$ 400,000,000.0
Facility term				5 years
Notice period for prepayment \| day				10
Default interest rate				5.00%
Repayment period upon change in control				30 days
Available borrowing capacity							41,300,000
Outstanding balance							358,700,000
Interest expense							$ 9,800,000	$ 1,400,000	$ 0
Term Loan \| New Letter Agreement with Sumitomo Dainippon Pharma, Co., Ltd. \| Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder
Related Party Transaction [Line Items]
Maximum borrowing commitment	$ 200,000,000.0
Facility term	5 years
LIBOR \| Term Loan \| Letter Agreement with Sumitomo Dainippon Pharma, Co., Ltd. \| Sumitomo Dainippon Pharma Co., Ltd. \| Majority Shareholder
Related Party Transaction [Line Items]
Variable interest rate				3.00%