Interest rate stated in the contractual debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-term debt Schedule of Long-term Debt (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Apr. 26, 2012	Apr. 14, 2011
Debt Instrument [Line Items]
Secured Debt				$ 1,400,000
Unsecured Debt			240,000	800,000
Other Long-term Debt	100	100
Long-term Debt	1,915,147	1,917,979
Long-term Debt, Current Maturities	(41,463)	(37,047)
Long-term debt, net of current maturities	1,873,684	1,880,932
Revolving Loan Facility [Member]
Debt Instrument [Line Items]
Secured Debt	0	0		500,000
Debt, Weighted Average Interest Rate	0.00%	0.00%
Term Loan 'A' Facility [Member]
Debt Instrument [Line Items]
Secured Debt	190,000	192,500		200,000
Debt, Weighted Average Interest Rate	2.70%	2.80%
Term Loan 'B' Facility [Member]
Debt Instrument [Line Items]
Secured Debt	684,690	684,937		700,000
Debt Instrument, Unamortized Discount	1,310	1,368
Debt, Weighted Average Interest Rate	4.00%	4.00%
7.5% Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured Debt	1,040,357	1,040,442
Debt Instrument, Unamortized Discount (Premium), Net	$ (357)	$ (442)
Debt Instrument, Interest Rate, Stated Percentage	7.50%	7.50%
9.25% Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.25%	9.25%