Variable Interest Entity Variable Interest Entity (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Concentration Risk [Line Items]
SEC Schedule, 12-04, Cash Dividends Paid to Registrant, 50 Percent or Less Owned Persons	$ 36
Revenue		$ 29,947	$ 29,956
Accounts receivable		$ 4,492	4,047
AKA [Member]
Concentration Risk [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Equity Method Investments		$ 100	100
Revenue		1,200	1,300
Accounts receivable		200	200
Deferred Revenue		200	$ 500
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 700

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

WESTELL TECHNOLOGIES INC 10-K