Summary of Significant Accounting Policies and Recent Accounting Pronouncements - Accumulated Other Comprehensive Loss (Components Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Loss
AOCI, foreign currency translation adjustment	$ (22,333)	$ (10,788)	$ (3,880)	$ (725)
Change in unrealized gain/loss on available-for-sale securities	2	(226)	86	326
Accumulated other comprehensive loss	(22,331)	(11,014)	(3,794)	$ (399)
Foreign currency translation adjustment	(11,545)	(6,908)	(3,155)
Change in unrealized gain/loss on available-for-sale securities	228	(312)	(240)
Other comprehensive loss	$ (11,317)	$ (7,220)	$ (3,395)