Operating Segment Results - (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net sales	$ 489,270	$ 498,738	$ 477,584
Operating Income (Loss)	(21,804)	(21,092)	(9,004)
Depreciation and amortization	46,120	47,231	46,195
Expenditures for long-lived assets	20,496	17,952	18,221
Assets	510,885	546,127
Investment in joint venture	32,701	31,802
Operating Segments | Mobile Solutions
Segment Reporting Information [Line Items]
Net sales	303,335	293,536	285,863
Operating Income (Loss)	(11,749)	(2,165)	9,039
Depreciation and amortization	29,156	28,192	28,769
Expenditures for long-lived assets	15,387	14,590	15,411
Assets	329,610	338,338
Operating Segments | Power Solutions
Segment Reporting Information [Line Items]
Net sales	185,948	205,204	191,800
Operating Income (Loss)	11,096	3,536	6,493
Depreciation and amortization	15,318	17,483	15,892
Expenditures for long-lived assets	3,643	2,401	2,200
Assets	147,155	178,129
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Operating Income (Loss)	(21,151)	(22,463)	(24,536)
Depreciation and amortization	1,646	1,556	1,534
Expenditures for long-lived assets	1,466	961	610
Assets	34,120	29,660
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	$ (13)	$ (2)	$ (79)