Industry Segment and Geographic Data, Reportable Segments (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financial information for reportable segment [Abstract]
Number of operating segments | Segment		3
Net sales	[1]	$ 1,358,272	$ 1,371,815	$ 1,298,816
Depreciation and amortization		29,022	28,298	27,243
Operating income (loss)		92,677	104,135	128,999
Investment in unconsolidated affiliates		24,050	41,745	44,087
Capital expenditures		28,633	25,956	25,875
Total assets		1,293,047	1,254,929	1,197,961
Vehicle Control [Member] | Reportable Segments [Member]
Financial information for reportable segment [Abstract]
Net sales	[1]	737,932	750,571	737,431
Depreciation and amortization		13,877	14,075	14,840
Operating income (loss)		71,327	74,153	97,029
Investment in unconsolidated affiliates		2,496	2,490	2,729
Capital expenditures		13,955	13,378	17,048
Total assets		620,569	618,789	604,016
Temperature Control [Member] | Reportable Segments [Member]
Financial information for reportable segment [Abstract]
Net sales	[1]	337,754	351,237	324,080
Depreciation and amortization		3,424	2,973	3,345
Operating income (loss)		17,343	26,459	30,077
Investment in unconsolidated affiliates		19,711	27,557	28,518
Capital expenditures		1,899	3,973	2,130
Total assets		274,657	254,137	234,771
Engineered Solutions [Member] | Reportable Segments [Member]
Financial information for reportable segment [Abstract]
Net sales	[1]	282,586	270,007	237,305
Depreciation and amortization		9,966	9,557	7,390
Operating income (loss)		19,944	18,713	19,982
Investment in unconsolidated affiliates		1,843	11,698	12,840
Capital expenditures		12,095	6,489	5,354
Total assets		292,080	289,518	272,791
Other [Member]
Financial information for reportable segment [Abstract]
Net sales	[1]	0	0	0
Depreciation and amortization		1,755	1,693	1,668
Operating income (loss)		(15,937)	(15,190)	(18,089)
Investment in unconsolidated affiliates		0	0	0
Capital expenditures		684	2,116	1,343
Total assets		$ 105,741	$ 92,485	$ 86,383

[1] There are no intersegment sales among our Vehicle Control, Temperature Control and Engineered Solutions operating segments.