Share-Based Compensation (Narrative) (Details) shares in Millions, $ in Millions	3 Months Ended
Jun. 30, 2022 USD ($) plan shares	Jun. 30, 2021 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of plans \| plan	2
Unrecognized compensation cost \| $	$ 112.1
Unrecognized compensation expense, period for recognition	3 years 1 month 6 days
Share-based compensation expense from acceleration, modification and subsequent remeasurement of awards \| $	$ 0.0	$ 1.4
Myovant 2016 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for grant (in shares) \| shares	2.2
2020 Inducement Equity Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for grant (in shares) \| shares	0.8

Share-based Compensation Arrangement by Share-based Compensation Payment Award, Number of Plans

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- Definition

Share-based Payment Arrangement, Settlement and Remeasurement of Awards Cost

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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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.

+ References

No definition available.

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