CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	[1],[2]	$ 1,137,913	$ 1,092,051	$ 1,116,143	[3],[4]
Cost of sales		806,113	779,264	789,487
Gross profit		331,800	312,787	326,656
Selling, general and administrative expenses		234,715	231,336	224,237
Restructuring and integration expenses		2,585	4,510	6,173
Other income (expense), net		(5)	4,327	1,275
Operating income		94,495	81,268	97,521
Other non-operating income (expense), net		2,587	(411)	1,250
Interest expense		5,286	4,026	2,329
Earnings from continuing operations before taxes		91,796	76,831	96,442
Provision for income taxes		22,745	19,977	52,812
Earnings from continuing operations		69,051	56,854	43,630
Loss from discontinued operations, net of income tax benefit of $3,912, $4,866 and $3,769		(11,134)	(13,851)	(5,654)
Net earnings		$ 57,917	$ 43,003	$ 37,976
Net earnings per common share - Basic:
Earnings from continuing operations (in dollars per share)		$ 3.09	$ 2.53	$ 1.92
Discontinued operations (in dollars per share)		(0.50)	(0.62)	(0.25)
Net earnings per common share - Basic (in dollars per share)		2.59	1.91	1.67
Net earnings per common share - Diluted:
Earnings from continuing operations (in dollars per share)		3.03	2.48	1.88
Discontinued operations (in dollars per share)		(0.49)	(0.60)	(0.24)
Net earnings per common share - Diluted (in dollars per share)		2.54	1.88	1.64
Dividends declared per share (in dollars per share)		$ 0.92	$ 0.84	$ 0.76
Average number of common shares (in shares)		22,378,414	22,456,480	22,726,491
Average number of common shares and dilutive common shares (in shares)		22,818,451	22,931,723	23,198,392

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

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

[3] Net sales and intersegment sales for 2017 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.

[4] Revenues for 2017 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.