Stock-Based Compensation - Narrative (Details) - Stock Incentive Plan 2015 - USD ($) $ in Thousands	6 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0
LTIP Performance Based PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	0
Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	0
Annual RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	34,211	38,307
Award vesting period (in years)	3 years
Annual PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	0	19,938
Award vesting period (in years)	3 years
Annual RSUs and Annual PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	34,211	58,245
Unrecognized stock compensation expense	$ 11,219

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

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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