Composition of Certain Financial Statement Captions - Summary of Equipment and Improvements (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 31, 2020
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 78,275	$ 78,710
Accumulated depreciation and amortization	(63,266)	(58,874)
Equipment and improvements, net	15,009	19,836
Computer Equipment
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	33,493	34,756
Internal-Use Software
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	17,882	17,796
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	11,540	12,477
Leasehold Improvements
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 15,360	$ 13,681

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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