7. FINANCIAL INSTRUMENTS - Available-for-sale investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Available-for-sale investments
Cost	$ 10,416
Total	10,337
Short-term Investments
Available-for-sale investments
Cost	7,018	$ 9,679
Gross Unrealized Gains		38
Gross Unrealized Losses	(26)
Total	6,992	9,717
Short-term Investments \| Certificates of Deposit
Available-for-sale investments
Cost	4,000	1,495
Gross Unrealized Gains		13
Gross Unrealized Losses	(11)
Total	3,989	1,508
Short-term Investments \| Supranational obligations
Available-for-sale investments
Cost	1,007	2,273
Gross Unrealized Gains		1
Gross Unrealized Losses	(7)
Total	1,000	2,274
Short-term Investments \| Bonds
Available-for-sale investments
Cost	2,011	5,911
Gross Unrealized Gains		24
Gross Unrealized Losses	(8)
Total	2,003	5,935
Other Long-term Investments
Available-for-sale investments
Cost	3,398	5,774
Gross Unrealized Gains		20
Gross Unrealized Losses	(53)	(2)
Total	3,345	5,792
Other Long-term Investments \| Certificates of Deposit
Available-for-sale investments
Cost	1,750	3,750
Gross Unrealized Gains		19
Gross Unrealized Losses	(18)	(1)
Total	1,732	3,768
Other Long-term Investments \| Supranational obligations
Available-for-sale investments
Cost	651	1,023
Gross Unrealized Losses	(17)	(1)
Total	634	1,022
Other Long-term Investments \| Bonds
Available-for-sale investments
Cost	997	1,001
Gross Unrealized Gains		1
Gross Unrealized Losses	(18)
Total	$ 979	$ 1,002

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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