Goodwill and Intangible Assets 5-Year Amortization (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 12,255
Finite-Lived Intangible Assets, Amortization Expense, Year Two	15,878
Finite-Lived Intangible Assets, Amortization Expense, Year Three	15,739
Finite-Lived Intangible Assets, Amortization Expense, Year Four	15,486
Finite-Lived Intangible Assets, Amortization Expense, Year Five	15,311
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	58,215
Finite-Lived Intangible Assets, Net	$ 132,884	$ 135,528