Long-term Debt - Long-term Debt Maturities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Long-term Debt, Fiscal Year Maturity
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months (2013)	$ 14,370
Long-term Debt, Maturities, Repayments of Principal in Year Two (2014)	12,030
Long-term Debt, Maturities, Repayments of Principal in Year Three (2015)	15,770
Long-term Debt, Maturities, Repayments of Principal in Year Four (2016)	17,020
Long-term Debt, Maturities, Repayments of Principal in Year Five (2017)	173,750
Long-term Debt, Maturities, Repayments of Principal after Year Five (Thereafter)	189,500
Long-term Debt	$ 422,440

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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

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