Debt - Credit Facilities (Details) - USD ($)				9 Months Ended
	Feb. 11, 2015	Feb. 11, 2014	Oct. 11, 2013	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Line of Credit Facility [Line Items]
Repayments of long-term debt				$ 250,000,000	$ 375,000,000
Term Loan
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 2,500,000,000
Required quarterly payments, percentage of original principal			0.25%
Repayments of long-term debt	$ 250,000,000	$ 375,000,000
Term Loan | LIBOR Rate Loans
Line of Credit Facility [Line Items]
Floor rate			0.75%
Revolver
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 250,000,000
Amount of letters of credit that can be issued under the Revolver			$ 50,000,000
Amount drawn on the Revolver				0		$ 0
Letters of credit issued under the revolver				$ 0		$ 0
Percentage of Revolver outstanding which triggers certain financial covenants				15.00%
Credit Facilities
Line of Credit Facility [Line Items]
Variable rate at end of period				3.25%
Percentage of consolidated total assets pledged as collateral				69.00%
Prime Rate | Credit Facilities | Base Rate Loans
Line of Credit Facility [Line Items]
Description of variable rate basis			Prime rate as designated by the administrative agent
Federal Funds Effective Rate | Credit Facilities | Base Rate Loans
Line of Credit Facility [Line Items]
Applicable margin			0.50%
Description of variable rate basis			Federal funds rate
LIBOR Rate | Credit Facilities | Base Rate Loans
Line of Credit Facility [Line Items]
Applicable margin			1.00%
Description of variable rate basis			LIBOR rate for one month
LIBOR Rate | Credit Facilities | LIBOR Rate Loans
Line of Credit Facility [Line Items]
Description of variable rate basis			LIBOR