Debt - Credit Facilities (Details) € in Millions, ¥ in Billions	1 Months Ended
	Oct. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2014 EUR (€)	Sep. 30, 2013 USD ($)	Sep. 30, 2013 JPY (¥)	Sep. 30, 2013 EUR (€)	Dec. 31, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2015 USD ($)
Line of Credit Facility [Line Items]
Total Commitments									$ 1,442,200,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Total Commitments	$ 250,000,000							$ 1,000,000,000
Senior Secured International Revolving Credit Facility
Line of Credit Facility [Line Items]
Total Commitments									$ 170,700,000
Debt Issuance Cost				$ 1,200,000
Deferred financing costs				$ 2,200,000
Revolving Credit Facility and Term Loan
Line of Credit Facility [Line Items]
Debt Issuance Cost	2,300,000							8,900,000
Deferred financing costs	2,400,000
Term Loans
Line of Credit Facility [Line Items]
Principal amount								$ 1,000,000,000
Debt Issuance Cost							$ 2,100,000
Increase in Term Loan							300,000,000
Reduction in Term Loan	$ 169,000,000
Deferred financing costs							$ 3,100,000
Minimum | LIBOR | Senior Secured International Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.50%	1.50%	1.50%
Minimum | LIBOR | Revolving Credit Facility and Term Loan
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.25%							1.75%
Maximum | LIBOR | Senior Secured International Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.50%	2.50%	2.50%
Maximum | LIBOR | Revolving Credit Facility and Term Loan
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.25%							2.75%
Borrowings in Euro and Pound | Senior Secured International Revolving Credit Facility
Line of Credit Facility [Line Items]
Deferred financing costs		$ 200,000
Increase in Credit Facility		$ 86,000,000	€ 63	$ 100,000,000		€ 75
Borrowings in Yen | Senior Secured International Revolving Credit Facility
Line of Credit Facility [Line Items]
Increase in Credit Facility				$ 25,000,000	¥ 2.5