Long-term Debt and Other Financing (Details2) - Revolving Credit Facility [Member] - USD ($)	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 1,500,000,000.0
Line of Credit Facility, Expiration Date	Mar. 31, 2019
Minimum amount of borrowing capacity for a fixed charge coverage ratio applies	$ 150,000,000
Line of Credit Facility, Current Borrowing Capacity	1,415,300,000.0
Outstanding borrowings on revolving credit facility	595,000,000	$ 605,000,000
Letters of credit, outstanding	73,300,000
Line of credit facility, remaining borrowing capacity	$ 747,000,000