LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Summary) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Long-term debt obligations
Long-term debt	$ 191,603	$ 127,730
Less current portion	35,050	25,256
Long-term debt, less current portion	156,553	102,474
Payments under long-term debt obligations
Due in one year or less	38,008
Due after one year through two years	36,955
Due after two years through three years	53,947
Due after three years through four years	2,643
Due after four years through five years	70,645
Total payments	202,198
Less amounts representing interest	10,595
Long-term debt	191,603	127,730
Credit Facility
Long-term debt obligations
Long-term debt	$ 70,000
Interest rate (as a percent)	1.40%
Payments under long-term debt obligations
Due in one year or less	$ 1,171
Due after one year through two years	1,513
Due after two years through three years	1,814
Due after three years through four years	2,074
Due after four years through five years	70,567
Total payments	77,139
Less amounts representing interest	7,139
Long-term debt	70,000
Term Loan
Long-term debt obligations
Long-term debt		70,000
Payments under long-term debt obligations
Long-term debt		70,000
Accounts receivable securitization program
Long-term debt obligations
Long-term debt	$ 35,000
Interest rate (as a percent)	1.00%
Payments under long-term debt obligations
Due in one year or less	$ 434
Due after one year through two years	606
Due after two years through three years	35,180
Total payments	36,220
Less amounts representing interest	1,220
Long-term debt	35,000
Notes payable
Long-term debt obligations
Long-term debt	$ 85,758	56,759
Weighted-average interest rate (as a percent)	1.90%
Payments under long-term debt obligations
Due in one year or less	$ 36,192
Due after one year through two years	34,619
Due after two years through three years	16,729
Due after three years through four years	339
Total payments	87,879
Less amounts representing interest	2,121
Long-term debt	85,758	56,759
Capital lease obligations
Long-term debt obligations
Long-term debt	$ 845	971
Weighted-average interest rate (as a percent)	5.80%
Payments under long-term debt obligations
Due in one year or less	$ 211
Due after one year through two years	217
Due after two years through three years	224
Due after three years through four years	230
Due after four years through five years	78
Total payments	960
Less amounts representing interest	115
Long-term debt	$ 845	$ 971