Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Foreign currency transaction and remeasurement gains/(losses)	$ 14.5	$ 0.0	$ 34.6	$ 0.0
Minimum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of fair value in excess of carrying amount	87.00%		87.00%
Maximum
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of fair value in excess of carrying amount	100.00%		100.00%