Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 10,871	$ 11,789
Intangible assets, amortization expense
Remaining of 2018	28,100
2019	35,800
2020	35,000
2021	33,700
2022	$ 32,000