Long-Term Debt (Details) (USD $)	3 Months Ended	9 Months Ended		0 Months Ended	3 Months Ended		9 Months Ended					3 Months Ended		9 Months Ended				0 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012	Apr. 13, 2011 Interest rate swap agreement	Sep. 30, 2013 Interest rate swap agreement	Sep. 30, 2012 Interest rate swap agreement	Sep. 30, 2013 Interest rate swap agreement	Sep. 30, 2012 Interest rate swap agreement	Dec. 31, 2012 Interest rate swap agreement	Sep. 30, 2013 Senior Notes due March 2016	Dec. 31, 2012 Senior Notes due March 2016	Sep. 30, 2013 Revolving credit line	Sep. 30, 2012 Revolving credit line	Sep. 30, 2013 Revolving credit line	Sep. 30, 2012 Revolving credit line	Dec. 31, 2012 Revolving credit line	Mar. 31, 2011 Revolving credit line	Jul. 30, 2013 Term Loan Facility	Sep. 30, 2013 Term Loan Facility	Dec. 31, 2012 Term Loan Facility	Mar. 31, 2011 Term loan	Dec. 31, 2011 Senior Notes due June 2017
Long-term debt
Long-term debt	$ 174,562,500	$ 174,562,500								$ 0	$ 57,012,000								$ 172,854,167	$ 0
Less: current portion	(1,750,000)	(1,750,000)	(4,608,000)
Long-term debt less current portion	171,104,167	171,104,167	52,404,000
Amount of term loan																		175,000,000
Uncommitted accordion option base amount																		20,000,000
Uncommitted accordion option multiplier of 1st lien net leverage																		4.0
Reference rate basis																		LIBOR
Interest rate margin (as a percent)																		5.00%
Interest rate floor (as a percent)																		1.25%
OID (as a percent)																		1.00%
OID																			1,750,000
Accumulated amortization of original issue discount																			41,667
Net debt issue costs																			3,400,000
Accumulated amortization																			82,359
Loss on early extinguishment of debt	1,648,546	1,648,546																	1,600,000
Maximum period after each fiscal year for prepayment of debt																			90 days
Prepayment of debt as a percentage of excess cash flow																			50.00%
First prepayment of debt as a percentage of excess cash flow, if lower leverage ratio is maintained																			25.00%
Second prepayment of debt as a percentage of excess cash flow, if lower leverage ratio is maintained																			0.00%
Amount of term loan																					66,000,000
Borrowing capacity																	10,000,000
Annual commitment fee (as a percent)														0.75%
Commitment fee												3,082	18,904	40,274	56,506
Amount outstanding under the revolving credit commitment												0		0		0						40,000,000
Maturity term				2 years
Initial notional amount				33,000,000
Variable rate basis for interest receivable				Three months LIBOR
Fixed rate of interest (as a percent)				1.143%
Fair value					0		0		122,032
Additional financing income related to the change in the fair value of derivatives					0	29,087	122,032	62,146
Maturities of long-term debt
Remainder of 2013	437,500	437,500
2014	1,750,000	1,750,000
2015	1,750,000	1,750,000
2016	1,750,000	1,750,000
2017 and thereafter	168,875,000	168,875,000
Total maturities	$ 174,562,500	$ 174,562,500								$ 0	$ 57,012,000								$ 172,854,167	$ 0