4. BALANCE SHEET DETAIL - Property and equipment, net (Details) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Mar. 31, 2022
Property and equipment, net:
Property and equipment, gross	$ 31,642,000		$ 31,642,000		$ 31,455,000
Less: Accumulated depreciation	(24,486,000)		(24,486,000)		(24,096,000)
Total property and equipment, net	7,156,000		7,156,000		7,359,000
Depreciation	196,000	$ 197,000	393,000	$ 384,000
Computer and other equipment
Property and equipment, net:
Property and equipment, gross	18,566,000		18,566,000		18,415,000
Software
Property and equipment, net:
Property and equipment, gross	4,428,000		4,428,000		4,425,000
Land
Property and equipment, net:
Property and equipment, gross	3,900,000		3,900,000		3,900,000
Building and building improvements
Property and equipment, net:
Property and equipment, gross	3,739,000		3,739,000		3,735,000
Furniture and fixtures
Property and equipment, net:
Property and equipment, gross	103,000		103,000		102,000
Leasehold improvements
Property and equipment, net:
Property and equipment, gross	$ 906,000		$ 906,000		$ 878,000