7. FINANCIAL INSTRUMENTS - Other information (Details) - USD ($)	6 Months Ended
Sep. 30, 2023	Mar. 31, 2023
Other information
Maximum maturity period of investment portfolio	3 years
Deferred tax asset related to unrecognized gains and losses on short-term and long-term investments	$ 1,000	$ 10,000

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