Note 5 - Supplemental Balance Sheet Information (Tables)

3 Months Ended

Mar. 31, 2022

Notes Tables

Cash, Cash Equivalents and Investments [Table Text Block]

	March 31,		December 31,
	2022		2021
Cash	$	5,968	$	8,329
Restricted cash		82		84
Total	$	6,050	$	8,413

Schedule of Inventory, Current [Table Text Block]

	March 31,		December 31,
	2022		2021
Raw materials	$	23,673	$	21,660
Work in process		3,521		4,227
Finished goods		9,186		7,302
Total	$	36,380	$	33,189

Property, Plant and Equipment [Table Text Block]

	March 31,			December 31,
	2022			2021
Land	$	1,273		$	1,273
Buildings and leasehold improvements		15,443			15,442
Machinery and equipment		64,137			63,780
Furniture and fixtures		2,654			2,588
Computer hardware and software		7,586			7,579
Construction in process		704			761
		91,797			91,423
Less: Accumulated depreciation		(69,024	)		(68,218	)
Property, plant and equipment, net	$	22,773		$	23,205

Schedule of Goodwill [Table Text Block]

	Battery & Energy			Communications
	Products			Systems		Total
Balance – December 31, 2021	$	26,575		$	11,493	$	38,068
Measurement period adjustment (1)		(30	)		-		(30	)
Effect of foreign currency translation		(112	)		-		(112	)
Balance – March 31, 2022	$	26,433		$	11,493	$	37,926

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	at March 31, 2022
			Accumulated
	Cost		Amortization		Net
Customer relationships	$	13,170	$	5,614	$	7,556
Patents and technology		5,637		5,137		500
Trade names		4,659		458		4,201
Trademarks		3,413		-		3,413
Other		1,500		127		1,373
Total other intangible assets	$	28,379	$	11,336	$	17,043

	at December 31, 2021
			Accumulated
	Cost		Amortization		Net
Customer relationships	$	13,214	$	5,484	$	7,730
Patents and technology		5,667		5,126		541
Trade names		4,670		436		4,234
Trademarks		3,413		-		3,413
Other		1,490		18		1,472
Total other intangible assets	$	28,454	$	11,064	$	17,390