Composition of Certain Financial Statement Captions - Summary of Equipment and Improvements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Mar. 31, 2021
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 80,318	$ 79,391
Accumulated depreciation and amortization	(69,500)	(64,852)
Equipment and improvements, net	10,818	14,539
Computer Equipment
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	36,335	35,244
Internal-Use Software
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	18,836	18,174
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	10,714	11,555
Leasehold Improvements
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 14,433	$ 14,418

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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