Summary of Significant Accounting Policies - (Gain) Loss on Foreign Currency Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accounting Policies [Abstract]
Foreign currency transaction losses (gains), net	$ 32,539	$ 23,500	$ 56,461	$ 25,591