4. BALANCE SHEET DETAIL - Accounts receivable, net (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Mar. 31, 2019
Accounts receivable, net:
Accounts receivable	$ 6,415	$ 7,441
Less: Allowances for doubtful accounts and other	(85)	(102)
Total accounts receivable, net	$ 6,330	$ 7,339

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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