Industry Segment and Geographic Data, Operating Income to Earnings (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Reconciliation of segment operating income to net earnings [Abstract]
Operating income										$ 81,268		$ 97,521		$ 98,789
Other non-operating income (expense), net										(411)		1,250	[1]	1,337	[1]
Interest expense										4,026		2,329		1,556
Earnings from continuing operations before taxes										76,831		96,442		98,570
Income tax expense										19,977		52,812		36,158
Earnings from continuing operations		$ 12,157	$ 19,273	$ 16,827	$ 8,597	$ (8,106)	$ 17,108	$ 18,261	$ 16,367	56,854		43,630		62,412
Discontinued operations, net of tax		(8,837)	(3,524)	(882)	(608)	(541)	(3,983)	(497)	(633)	(13,851)		(5,654)		(1,982)
Net earnings		3,320	15,749	15,945	7,989	(8,647)	13,125	17,764	15,734	43,003		37,976		60,430
Revenues [Abstract]
Revenues		246,970	$ 296,619	$ 286,636	$ 261,826	239,978	$ 281,058	$ 312,729	$ 282,378	1,092,051	[2],[3]	1,116,143	[2],[3],[4],[5]	1,058,482	[2],[3],[4],[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	254,574				259,056				254,574		259,056		243,349
United States [Member]
Revenues [Abstract]
Revenues	[2]									974,360		1,001,003	[5]	952,019	[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	198,494				202,875				198,494		202,875		204,592
Canada [Member]
Revenues [Abstract]
Revenues	[2]									57,335		52,005	[5]	53,324	[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	2,718				2,017				2,718		2,017		1,344
Mexico [Member]
Revenues [Abstract]
Revenues	[2]									23,650		24,521	[5]	24,429	[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	4,012				4,449				4,012		4,449		3,877
Europe [Member]
Revenues [Abstract]
Revenues	[2]									13,578		14,088	[5]	14,703	[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	16,880				18,530				16,880		18,530		13,612
Other Foreign [Member]
Revenues [Abstract]
Revenues	[2]									23,128		24,526	[5]	14,007	[5]
Long-lived assets [Abstract]
Long-lived assets	[6]	$ 32,470				$ 31,185				$ 32,470		$ 31,185		$ 19,924

[1] Net periodic benefit credit (cost) has been reclassified from selling, general and administrative expenses to other non-operating income (expense), net on our consolidated statement of operations upon adoption of ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, see Note 1, "Summary of Significant Accounting Policies" for additional information.

[2] Revenues are attributed to countries based upon the location of the customer.

[3] Segment net sales include intersegment sales in our Engine Management and Temperature Control segments.

[4] Net sales and intersegment sales for 2017 and 2016 have not been restated and are reported under accounting standards in effect in the period presented, as we adopted ASU 2014-09, Revenue from Contracts with Customers, on January 1, 2018 using the modified retrospective method.

[5] Revenues for 2017 and 2016 have not been restated and are reported under accounting standards in effect in the period presented, as we adopted ASU 2014-09, Revenue from Contracts with Customers, on January 1, 2018 using the modified retrospective method.

[6] Long-lived assets are attributed to countries based upon the location of the assets.