7. FINANCIAL INSTRUMENTS - Other information (Details) - USD ($)	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Other information
Maximum maturity period of investment portfolio	3 years
Deferred tax liability related to unrecognized gains and losses on short-term and long-term investments		$ 15,000
Deferred tax asset related to unrecognized gains and losses on short-term and long-term investments	$ 22,000

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from investments (excludes investments in subsidiaries and equity method investments).

No definition available.

Name:	us-gaap_DeferredTaxAssetsInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant