Goodwill and Acquired Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of acquired intangible assets	$ 6,711	$ 6,752	$ 13,427	$ 13,532
Future amortization expense to be recognized in remainder of 2016	13,100		13,100
Future amortization expense 2017	27,800		27,800
Future amortization expense 2018	23,700		23,700
Future amortization expense 2019	21,700		21,700
Future amortization expense 2020	$ 17,700		$ 17,700