CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net sales	$ 273,949	$ 255,374	$ 525,321	$ 478,977
Cost of goods sold	168,767	163,731	328,368	309,552
Gross profit	105,182	91,643	196,953	169,425
Selling, general, and administrative expenses	40,816	36,700	81,761	78,588
Technical and research expenses	9,242	10,198	19,491	20,515
Restructuring expenses, net	899	2,589	1,383	11,162
Operating income	54,225	42,156	94,318	59,160
Interest expense, net	4,631	4,621	9,048	8,909
Other (income)/expense, net	930	726	(278)	2,178
Income before income taxes	48,664	36,809	85,548	48,073
Income tax expense	14,405	6,966	21,881	10,331
Net income	34,259	29,843	63,667	37,742
Net income/(loss) attributable to the noncontrolling interest	205	(59)	423	178
Net income attributable to the Company	$ 34,054	$ 29,902	$ 63,244	$ 37,564
Earnings per share attributable to Company shareholders - Basic	$ 1.05	$ 0.93	$ 1.96	$ 1.17
Earnings per share attributable to Company shareholders - Diluted	$ 1.05	$ 0.93	$ 1.96	$ 1.16
Shares of the Company used in computing earnings per share:
Basic	32,299	32,257	32,286	32,239
Diluted	32,311	32,273	32,298	32,255
Dividends declared per share, Class A and Class B	$ 0.18	$ 0.17	$ 0.36	$ 0.34