LONG TERM DEBT (Details) (USD $)	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2011	Mar. 31, 2011	Sep. 30, 2012	Dec. 31, 2011	Mar. 11, 2011
Long-Term Debt
Long-term debt			$ 508,985,000	$ 508,033,000
Less current portion			(7,775,000)	(8,065,000)
Long-term debt, less current portion			501,210,000	499,968,000
On or prior to November 15, 2013
Long-Term Debt
Maximum percentage of the aggregate principal amount up to which the notes may be redeemed			35.00%
Percentage of the aggregate principal amount at which the notes may be redeemed			107.125%
On or after November 15, 2014
Long-Term Debt
Minimum notice period that the entity must provide for the redemption of the debt instrument (in days)			30
Maximum notice period that the entity must provide for the redemption of the debt instrument (in days)			60
Twelve month period beginning November 15, 2014
Long-Term Debt
Percentage of the aggregate principal amount at which the notes may be redeemed			103.563%
Twelve month period beginning November 15, 2015
Long-Term Debt
Percentage of the aggregate principal amount at which the notes may be redeemed			101.781%
Period beginning November 15, 2016 and thereafter through November 15, 2018
Long-Term Debt
Percentage of the aggregate principal amount at which the notes may be redeemed			100.00%
October 1, 2011 to September 30, 2012
Long-Term Debt
Consolidated interest coverage ratio			3.25
October 1, 2012 and thereafter until maturity
Long-Term Debt
Consolidated interest coverage ratio			3.50
Total leverage ratio			4.00
Prior to December 31, 2011
Long-Term Debt
Total leverage ratio			5.00
January 1, 2012 to September 30, 2012
Long-Term Debt
Total leverage ratio			4.50
Revolving Credit Facility
Long-Term Debt
Maximum borrowing capacity			100,000,000
Interest, base rate			LIBOR
Interest rate margin (as a percent)			3.75%
Maximum annual capital expenditure as a percentage of consolidated net revenue of preceding fiscal year			7.50%
Additional maximum rollover from prior year's capital expenditure allowance			15,000,000
Balance available under the credit facility			99,500,000
Standby letters of credit
Long-Term Debt
Balance available under the credit facility			500,000
Term Loan
Long-Term Debt
Long-term debt			294,050,000	297,000,000
Issuance of debt				300,000,000
Quarterly principal payments		750,000
Repayments of debt			700,000
Fees related to the amendment of the credit agreement	4,100,000
Reduction in the interest rate margin applicable to the Term Loan (as a percent)					0.75%
Interest, base rate	LIBOR		LIBOR
Interest rate margin (as a percent)			3.00%		3.00%
LIBOR floor applicable to term loans under Credit Agreement, prior to amendment (as a percent)					1.50%
LIBOR floor applicable to term loans under Credit Agreement (as a percent)					1.00%
Interest rate (as a percent)			4.00%
7.125% Senior Notes due 2018
Long-Term Debt
Long-term debt			200,000,000	200,000,000
Interest rate stated percentage			7.125%
Subordinated seller notes, non-collateralized, net of unamortized discounts with principal and interest payable in either monthly, quarterly or annual installments, maturing through November, 2016
Long-Term Debt
Long-term debt			$ 14,935,000	$ 11,033,000
Interest rate, minimum (as a percent)			2.00%
Interest rate, maximum (as a percent)			6.50%