Share-based Compensation - Schedule of Fair Value Assumptions (Details) - USD ($)	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	$ 0
Expected term (years)	6 years 1 month 6 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	37.10%
Risk-free interest rate	0.80%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	38.90%
Risk-free interest rate	1.90%
2019 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	$ 0
Expected volatility	35.90%
Expected term (years)	15 days
Risk-free interest rate	1.60%
Management Incentive Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	$ 0	$ 0	$ 0
Expected volatility			50.00%
Expected term (years)			2 years 6 months
Risk-free interest rate			2.34%
Management Incentive Unit \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	35.00%	50.00%
Expected term (years)	6 months	1 year
Risk-free interest rate	1.86%	2.33%
Management Incentive Unit \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	55.00%	60.00%
Expected term (years)	1 year 3 months	1 year 6 months
Risk-free interest rate	2.09%	2.40%
Appreciation Unit \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	$ 0.00
Expected volatility	35.00%	50.00%	50.00%
Expected term (years)	6 months	1 year	2 years 6 months
Risk-free interest rate	1.86%	2.33%	2.34%
Appreciation Unit \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	$ 0.00
Expected volatility	55.00%	60.00%
Expected term (years)	1 year 3 months	1 year 6 months
Risk-free interest rate	2.09%	2.40%

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

+ References

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

+ 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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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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