Debt (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Long-term Debt, by Maturity
2013	$ 174,648
2014	631,345
2015	240,681
2016	87,223
2017	125,999
Thereafter through 2037	725,257
Long Term Debt Before Unamortized Discount	1,985,153
Unamortized discount	(16,756)
Total scheduled debt principal payments	1,968,397
Revolving Credit Facility
Long-term Debt, by Maturity
2014	78,000
Term Loan Facility
Long-term Debt, by Maturity
2014	$ 175,000

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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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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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings, before unamortized discount, as of the balance sheet date.

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