Goodwill and Intangible Assets - Estimated Future Amortization Expense by Year (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 16,400	$ 13,200	$ 14,100
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2017	17,212
2018	17,040
2019	16,883
2020	16,841
2021	$ 16,684