Intangible Assets and Goodwill (Goodwill) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2015 USD ($)
Goodwill [Roll Forward]
Beginning balance as of December 31, 2014	$ 551,196
Subsequent goodwill adjustments	(5,528)
Ending balance as of June 30, 2015	$ 545,668