Recently Issued Accounting Standards Recently Issued Accounting Standards - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of net sales		$ 698,437	$ 566,852	$ 524,505
Cumulative effect recognized on initial application of the new guidance	$ 374,783	374,783	$ 325,466
Difference between Revenue Guidance in Effect before and after Topic 606 | Minimum | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect on revenue	17,000
Effect of net sales	15,000
Cumulative effect recognized on initial application of the new guidance	1,000	1,000
Difference between Revenue Guidance in Effect before and after Topic 606 | Maximum | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect on revenue	23,000
Effect of net sales	19,000
Cumulative effect recognized on initial application of the new guidance	$ 2,500	$ 2,500