Intangible Assets - Intangible Assets, Other than Capitalized Software Development Costs (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 31, 2021
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	$ 88,450	$ 130,950
Accumulated amortization	(57,948)	(94,250)
Net intangible assets	30,502	36,700
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	39,200	39,200
Accumulated amortization	(28,086)	(26,349)
Net intangible assets	11,114	12,851
Trade Names
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	250	250
Accumulated amortization	(92)	(67)
Net intangible assets	158	183
Computer Software, Intangible Asset
Finite Lived Intangible Assets [Line Items]
Gross carrying amount	49,000	91,500
Accumulated amortization	(29,770)	(67,834)
Net intangible assets	$ 19,230	$ 23,666