CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
CONSOLIDATED STATEMENTS OF EARNINGS [Abstract]
Revenue	$ 335,827	$ 323,090	$ 695,529	$ 673,767
Cost of products sold	224,233	220,876	468,322	459,660
Selling and administrative expenses	75,841	60,089	144,557	137,421
Operating income	35,753	42,125	82,650	76,686
Interest expense	3,322	3,608	6,755	7,915
Earnings before income taxes	32,431	38,517	75,895	68,771
Income taxes	6,495	7,897	18,291	17,378
Net earnings	$ 25,936	$ 30,620	$ 57,604	$ 51,393
Weighted average number of common shares outstanding:
Basic (in shares)	42,135	42,305	42,199	42,294
Diluted (in shares)	42,267	42,322	42,328	42,315
Earnings per common share:
Basic (in dollars per share)	$ 0.62	$ 0.72	$ 1.37	$ 1.22
Diluted (in dollars per share)	0.61	0.72	1.36	1.21
Dividends declared per common share (in dollars per share)	$ 0.39	$ 0.39	$ 0.78	$ 0.78