Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment			3
Segment Information
Net sales	$ 304,853	$ 308,007	$ 564,097	$ 552,786
Income (Loss) from Operations	53,653	61,433	83,676	94,117
Total Assets	1,069,918	1,085,887	1,069,918	1,085,887	$ 1,021,663
Cash and cash equivalent	141,731	155,035	141,731	155,035	160,180	$ 168,514
Intersegment elimination
Segment Information
Net sales	8,373	7,626	15,568	15,127
Administrative and all other
Segment Information
Income (Loss) from Operations	(1,420)	(1,573)	(3,235)	(2,763)
Total Assets	(325,644)	(194,107)	(325,644)	(194,107)	(280,430)
Cash and cash equivalent	98,400	71,800	98,400	71,800	113,600
North America
Segment Information
Net sales	259,073	259,822	480,504	466,034
Income (Loss) from Operations	50,100	59,991	82,864	96,444
Total Assets	1,194,318	1,042,765	1,194,318	1,042,765	1,119,012
North America | Intersegment elimination
Segment Information
Net sales	466	578	807	1,206
Europe
Segment Information
Net sales	43,648	45,784	79,428	82,077
Income (Loss) from Operations	4,725	3,688	4,341	2,099
Total Assets	173,791	208,609	173,791	208,609	157,437
Europe | Intersegment elimination
Segment Information
Net sales	631	251	1,089	600
Asia/Pacific
Segment Information
Net sales	2,132	2,401	4,165	4,675
Income (Loss) from Operations	248	(673)	(294)	(1,663)
Total Assets	27,453	28,620	27,453	28,620	$ 25,644
Asia/Pacific | Intersegment elimination
Segment Information
Net sales	$ 7,276	$ 6,797	$ 13,672	$ 13,321