Long-Term Debt (Details Textual) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Sep. 16, 2011	May 13, 2011
Long-Term Debt (Textual) [Abstract]
Total credit facility	$ 2,081,955,000	$ 2,081,955,000	$ 2,240,537,000
Debt discount on term loans and revolving credit facilities	25,100,000	25,100,000		25,100,000
Less: Letters of credit drawn					30,000,000
Swingline borrowings					30,000,000
Amortization rate per annum		1.00%
Date of Amortization		Mar. 31, 2012
Agreement maturity date		May 01, 2019
Amortization costs	2,500,000	7,600,000
Senior Notes issued						610,000,000
Amount repaid under outstanding term loan facility		575,800,000
Percentage of Senior Notes to be redeemed prior to May 1, 2014		35.00%
Percentage of Senior Notes to be redeemed prior to May 1, 2015		100.00%
J P Morgan [Member]
Long-Term Debt (Textual) [Abstract]
Interest on LIBOR-based loan		3.00%
First Lien Facility [Member]
Long-Term Debt (Textual) [Abstract]
Total credit facility					1,325,000,000
Debt discount on term loans and revolving credit facilities					13,500,000
Amount outstanding	1,314,000,000	1,314,000,000
Interest on LIBOR-based borrowings		4.50%
Interest on LIBOR-based borrowings		LIBOR plus 4.5 %
LIBOR floor		1.25%
Interest on Base Rate-based borrowings		3.50%
Base Rate Floor		2.25%
Interest on borrowings, per annum	5.75%	5.75%
Security interest granted		66.00%
Federal Funds Rate	1.00%	1.00%
Federal Funds Rate		Federal Reserve Bank Rate plus 1/2 of 1.0%
Base Rate	1.00%	1.00%
Base Rate		30 day LIBOR plus 1.0%
Agreement maturity date		Sep. 01, 2018
Revolving Credit Facility [Member]
Long-Term Debt (Textual) [Abstract]
Total credit facility					300,000,000
Amount outstanding	0	0
LIBOR floor		1.00%
Base Rate Floor		2.00%
Interest on borrowings, per annum	5.75%	5.75%
Federal Funds Rate	1.00%	1.00%
Federal Funds Rate		Federal Reserve Bank Rate plus 1/2 of 1.0%
Base Rate	1.00%	1.00%
Base Rate		30 day LIBOR plus 1.0%
Net Leverage Ratio Minimum	100.00%	100.00%
Net Leverage Ratio Maximum	700.00%	700.00%
Agreement maturity date		Sep. 01, 2016
Second Lien Facility [Member]
Long-Term Debt (Textual) [Abstract]
Total credit facility	790,000,000	790,000,000
Debt discount on term loans and revolving credit facilities					12,000,000
Amount outstanding	$ 790,000,000	$ 790,000,000
Interest on LIBOR-based borrowings		6.00%
Interest on LIBOR-based borrowings		LIBOR plus 6.0 %
LIBOR floor		1.50%
Interest on Base Rate-based borrowings on Second Lien Facility		Base Rate plus 5.0 %
Interest on Base Rate-based borrowings		5.00%
Base Rate Floor		2.50%
Interest on borrowings, per annum	7.50%	7.50%
Security interest granted		66.00%
Federal Funds Rate	1.00%	1.00%
Federal Funds Rate		Federal Reserve Bank Rate plus 1/2 of 1.0%
Base Rate	1.00%	1.00%
Base Rate		30 day LIBOR plus 1.0%
Agreement maturity date		Sep. 01, 2019