LONG TERM DEBT (Details) (USD $)			6 Months Ended				6 Months Ended			6 Months Ended						6 Months Ended		12 Months Ended		3 Months Ended	6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Revolving credit facility	Dec. 31, 2013 Revolving credit facility	Jun. 30, 2013 Revolving credit facility	Jun. 30, 2014 Standby letters of credit	Jun. 30, 2014 Term loan	Dec. 31, 2013 Term loan	Jun. 30, 2013 Term loan	Jun. 30, 2014 Term loan Minimum	Jun. 30, 2014 Term loan Maximum	Jun. 30, 2014 7.125% Senior notes due 2018	Dec. 31, 2013 7.125% Senior notes due 2018	Jun. 30, 2014 7.125% Senior notes due 2018 Level 2	Dec. 31, 2013 7.125% Senior notes due 2018 Level 2	Jun. 30, 2014 7.125% Senior notes due 2018 Prior to November 15, 2014	Jun. 30, 2014 Subordinated seller notes, non-collateralized, net of unamortized discount with principal and interest payable in either monthly, quarterly or annual installments at effective interest rates ranging from 2.00% to 4.0%, maturing through November 2018	Dec. 31, 2013 Subordinated seller notes, non-collateralized, net of unamortized discount with principal and interest payable in either monthly, quarterly or annual installments at effective interest rates ranging from 2.00% to 4.0%, maturing through November 2018	Jun. 30, 2013 Previous credit agreement	Jun. 30, 2013 New credit agreement	Jun. 30, 2014 New credit agreement Minimum	Jun. 30, 2014 New credit agreement Maximum
Long-Term Debt
Total Debt	$ 539,889,000	$ 468,259,000	$ 90,000,000	$ 25,000,000			$ 219,375,000	$ 222,188,000				$ 200,000,000	$ 200,000,000	$ 210,000,000	$ 213,300,000		$ 30,514,000	$ 21,071,000
Less current portion	(23,638,000)	(15,998,000)
Long term debt	516,251,000	452,261,000
Interest rate stated percentage												7.125%	7.125%
Effective interest rate, minimum																	2.00%	2.00%
Effective interest rate, maximum																	4.00%	4.00%
Term of agreement																				5 years
Maximum borrowing capacity			200,000,000		200,000,000				225,000,000										400,000,000	425,000,000
Interest, base rate			LIBOR				LIBOR
Interest rate margin (as a percent)			1.75%				1.75%
Pre-tax non-cash charge related to the write-off of existing debt issuance costs associated with its previous credit agreement																				6,600,000
Prepayment penalties																				0
Balance available under the credit facility			106,400,000
Amounts outstanding under the credit facility			90,000,000
Amount outstanding						3,600,000
Outstanding amount							219,400,000
Quarterly principal payment percentage										0.625%	3.75%
Mandatory prepayment							$ 0
Redemption period, end date																Nov. 14, 2014
Percentage of the outstanding principal amount plus and amount equal to the unaccrued interest at which the notes may be redeemed																103.60%
Consolidated interest coverage ratio																					3.50
Total leverage ratio																						4.00