Goodwill and Other Intangible Assets Schedule of Finite-Lived Intangible Assets, Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Amortization of Intangible Assets [Line Items]
Amortization of intangible assets	$ 4,860	$ 4,930	$ 14,600	$ 14,920
Cost of Sales [Member] | Technology and Other [Member]
Amortization of Intangible Assets [Line Items]
Amortization of intangible assets	1,230	1,280	3,680	3,990
Selling, General and Administrative Expenses [Member] | Customer Relationships [Member]
Amortization of Intangible Assets [Line Items]
Amortization of intangible assets	$ 3,630	$ 3,650	$ 10,920	$ 10,930