Composition of Certain Financial Statement Captions - Summary of Equipment and Improvements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 78,710	$ 72,817
Accumulated depreciation and amortization	(58,874)	(51,413)
Equipment and improvements, net	19,836	21,404
Computer Equipment
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	34,756	28,923
Internal-Use Software
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	17,796	17,084
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	12,477	11,660
Leasehold Improvements
Property Plant And Equipment [Line Items]
Equipment and improvements, gross	$ 13,681	$ 15,150

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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