Goodwill and Acquired Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of acquired intangible assets	$ 7,753	$ 6,711	$ 15,322	$ 13,427
Future amortization expense to be recognized in remainder of 2017	15,500		15,500
Future amortization expense 2018	31,400		31,400
Future amortization expense 2019	32,800		32,800
Future amortization expense 2020	29,500		29,500
Future amortization expense 2021	$ 24,100		$ 24,100