PROPERTY AND EQUIPMENT: (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 44,284	$ 44,786
Less accumulated depreciation and amortization	32,327	25,465
Property and equipment, net of accumulated depreciation and amortization	11,957	19,321
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	26,024	25,614
Data processing equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9,053	9,499
Office furniture and other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 9,207	$ 9,673