INCOME TAXES, Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020
Deferred tax assets [Abstract]
Accrued vacation	$ 2,537	$ 1,966
Deferred revenue	4,227	3,175
Allowance for credit losses	1,048	792
Restricted stock	772	1,575
Other deferred tax assets	1,552	608
Accrued bonus	2,277	2,426
Lease liabilities	2,476	2,550
Other credits and carryforwards	0	1,385
Gross deferred tax assets	14,889	14,477
Less: valuation allowance	0	(1,385)
Net deferred tax assets	14,889	13,092
Deferred tax liabilities [Abstract]
Property and equipment	(2,391)	(2,102)
Operating leases	(6,948)	(10,098)
Prepaid expenses	(912)	(817)
Right-of-use assets	(2,419)	(2,535)
Tax deductible goodwill	(751)	(270)
Total deferred tax liabilities	(13,421)	(15,822)
Net deferred tax asset	$ 1,468
Net deferred tax liability		$ (2,730)