Debt (Narrative) (Details) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended				1 Months Ended				12 Months Ended		1 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended		1 Months Ended				1 Months Ended		12 Months Ended					1 Months Ended	12 Months Ended			3 Months Ended	12 Months Ended
	Nov. 30, 2012	May 31, 2011	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Sep. 16, 2013	May 31, 2011 Term B Loan Facility [Member]	Sep. 30, 2010 Term B Loan Facility [Member]	Nov. 30, 2012 Term C Loan Facility [Member]	Sep. 30, 2010 Term C Loan Facility [Member]	Dec. 31, 2012 Term C Loan Facility [Member]	Dec. 31, 2013 Term C Loan Facility [Member]	Nov. 30, 2012 Senior Unsecured Notes Due 2022 [Member]	Dec. 31, 2013 Senior Unsecured Notes Due 2022 [Member]	Dec. 31, 2012 Senior Unsecured Notes Due 2022 [Member]	May 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2013 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2012 Senior Unsecured Notes Due 2021 [Member]	Sep. 30, 2010 Senior Unsecured Notes Due 2018 [Member]	Dec. 31, 2013 Senior Unsecured Notes Due 2018 [Member]	Dec. 31, 2012 Senior Unsecured Notes Due 2018 [Member]	Sep. 30, 2013 Revolving Credit Facility [Member]	Sep. 30, 2010 Revolving Credit Facility [Member]	Dec. 31, 2013 Revolving Credit Facility [Member]	Sep. 16, 2013 Revolving Credit Facility [Member]	Sep. 30, 2013 Credit-linked Revolving Facility [Member]	Sep. 30, 2010 Credit-linked Revolving Facility [Member]	Dec. 31, 2013 Credit-linked Revolving Facility [Member]	Dec. 31, 2012 Credit-linked Revolving Facility [Member]	Sep. 16, 2013 Credit-linked Revolving Facility [Member]	Sep. 10, 2013 Credit-linked Revolving Facility [Member]	Apr. 25, 2013 Credit-linked Revolving Facility [Member]	Sep. 30, 2013 Term C-2 Loan Facility [Member]	Dec. 31, 2013 Term C-2 Loan Facility [Member]	Dec. 31, 2012 Term C-2 Loan Facility [Member]	Dec. 31, 2013 Amended Credit Agreement [Member]	Dec. 31, 2013 Accounts Receivable Securitization Facility [Member]	Dec. 31, 2013 Accounts Receivable Securitization Facility [Member]	Aug. 28, 2013 Accounts Receivable Securitization Facility [Member]
Debt Instrument [Line Items]
Senior notes														$ 500,000,000			$ 400,000,000			$ 600,000,000
Interest rate, stated percentage														4.625%	4.625%	4.625%	5.875%	5.875%	5.875%	6.625%	6.625%	6.625%
Debt instrument, redemption price, percentage															100.00%			100.00%			100.00%
Line of credit facility, prepayment										400,000,000																	100,000,000											50,000,000
Year of maturity								Apr. 02, 2014						Nov. 15, 2022	Nov. 15, 2022	Nov. 15, 2022	Jun. 15, 2021	Jun. 15, 2021	Jun. 15, 2021	Oct. 15, 2018	Oct. 15, 2018	Oct. 15, 2018
Accelerated amortization of deferred financing costs	3,000,000	3,000,000	1,000,000	1,000,000	3,000,000	3,000,000
Deferred financing costs, gross	8,000,000	8,000,000					2,000,000
Senior credit facilities								516,000,000				977,000,000	0												0				0	50,000,000					978,000,000	0		50,000,000	50,000,000
Revolving credit facility, borrowing capacity																								600,000,000		600,000,000		228,000,000	23,000,000		81,000,000	81,000,000	200,000,000							135,000,000
Line of credit facility, current borrowing capacity																																						129,000,000	129,000,000
Credit facility, expiration date									Apr. 02, 2014	Oct. 31, 2016	Oct. 31, 2016	Oct. 31, 2016											Oct. 31, 2015	Oct. 31, 2015			Apr. 02, 2014	Apr. 02, 2014	Apr. 02, 2014	Apr. 02, 2014				Oct. 31, 2016	Oct. 31, 2016				Aug. 28, 2016
Cross default covenant to other debt																																					40,000,000
Accounts receivable transferred for securitization				$ 199,000,000