Composition of Certain Financial Statement Captions - Summary of Equipment and Improvements (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 80,160	$ 79,391
Accumulated depreciation and amortization	(66,684)	(64,852)
Equipment and improvements, net	13,476	14,539
Computer Equipment
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	35,563	35,244
Internal-Use Software
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	18,699	18,174
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	11,182	11,555
Leasehold Improvements
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 14,716	$ 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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