Debt (Details 2) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Debt
Total long-term debt	$ 244,102,161	$ 195,977,937
Unamortized debt discount	(4,733,296)	(5,936,004)
Total long-term debt	239,368,865	190,041,933
Estimated annual maturities for long-term debt
2015	244,102,161
Total long-term debt	244,102,161	195,977,937
Senior Credit Agreement
Debt
Weighted average interest rate (as a percent)	2.76%
Total long-term debt	69,102,161	20,977,937
Estimated annual maturities for long-term debt
Total long-term debt	69,102,161	20,977,937
Second Lien Credit Agreement
Debt
Interest rate of debt instrument (as a percent)	12.50%
Total long-term debt	175,000,000	175,000,000
Estimated annual maturities for long-term debt
Total long-term debt	$ 175,000,000	$ 175,000,000

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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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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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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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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Reflects the calculation as of the balance sheet date of the average interest rate weighted by the amount of long-term debt outstanding by type or by instrument at that time.

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