Segment Information (Net Sales by Region or Origin and Long-Lived Assets by Region of Domicile) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:	$ 265,201	$ 296,792	$ 255,184	$ 215,401	$ 226,034	$ 260,784	$ 224,255	$ 187,160	$ 1,032,578	$ 898,233	$ 837,097
Long-lived assets	91,161				80,132				91,161	80,132	80,248
North America
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:									1,018,406	881,432	825,497
Long-lived assets	90,685				79,590				90,685	79,590	79,544
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:									14,172	16,801	11,600
Long-lived assets	$ 476				$ 542				$ 476	$ 542	$ 704