Segment Information Segment Information - Net Sales by Destination of Product Delivery (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales	$ 920,016		$ 842,861		$ 1,850,944	$ 1,671,154
Net sales related to the U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales		$ 234,118		$ 243,815	464,521	449,325
Net sales attributed to all foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales		$ 685,898		$ 599,046	$ 1,386,423	$ 1,221,829