Fair Value of Assets and Liabilities - Summary of Liabilities Recorded at Carrying Value (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair value and carrying value of the Company's debt instruments
Current notes payable - Fair value	$ 26,773	$ 34,212
Notes payable - Carrying value	26,773	34,212
Long-term debt - Fair Value	567,918	630,450
Long-term debt - Carrying value	561,595	617,534
Total debt instruments - Fair value	594,691	664,662
Total debt instruments - Carrying value	$ 588,368	$ 651,746

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

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Fair value portion of notes payable.

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