Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Net sales	$ 410,281	$ 326,076	$ 757,922	$ 609,744
Cost of sales	213,835	176,276	399,195	330,278
Gross profit	196,446	149,800	358,727	279,466
Operating expenses:
Research and development and other engineering	14,169	12,191	28,758	25,573
Selling	33,167	26,834	63,990	55,361
General and administrative	47,410	38,636	95,975	77,107
Total operating expenses	94,746	77,661	188,723	158,041
Net gain on disposal of assets	(28)	(73)	(108)	(137)
Income from operations	101,728	72,212	170,112	121,562
Interest expense, net and other	(2,636)	(151)	(4,413)	(2,684)
Income before taxes	99,092	72,061	165,699	118,878
Provision for income taxes	26,609	18,582	42,827	28,573
Net income	72,483	53,479	122,872	90,305
Translation adjustment	7,505	4,525	(1,759)	(3,069)
Unamortized pension adjustments	(102)	(213)	390	61
Unrealized gains (losses) on derivative instruments	(7)	0	19	0
Comprehensive net income	$ 79,879	$ 57,791	$ 121,522	$ 87,297
Net income per common share:
Basic	$ 1.67	$ 1.23	$ 2.83	$ 2.06
Diluted	$ 1.66	$ 1.22	$ 2.82	$ 2.05
Number of shares outstanding
Basic	43,434,000	43,471,000	43,406,000	43,787,000
Diluted	43,641,000	43,663,000	43,620,000	43,980,000
Cash dividends declared per common share	$ 0.25	$ 0.23	$ 0.48	$ 0.46

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use; (3) to conduct internal product testing; (4) or to provide engineering support to customers in the form of testing services or product uses, specifications or requirements.

No definition available.