LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Long-term debt obligations
Long-term debt	$ 133,976	$ 155,985
Less current portion	37,030	43,044
Long-term debt, less current portion	96,946	112,941
Payments under long-term debt obligations
Due in one year or less	39,651
Due after one year through two years	31,727
Due after two years through three years	23,102
Due after three years through four years	46,605
Due after four years through five years	222
Due after five years	365
Total payments	141,672
Less amounts representing interest	7,696
Long-term debt	133,976	155,985
Term Loan
Long-term debt obligations
Long-term debt	90,000	95,000
Interest rate (as a percent)	1.70%
Payments under long-term debt obligations
Due in one year or less	14,026
Due after one year through two years	16,489
Due after two years through three years	19,083
Due after three years through four years	46,389
Total payments	95,987
Less amounts representing interest	5,987
Long-term debt	90,000	95,000
Notes payable
Long-term debt obligations
Long-term debt	30,142	37,756
Weighted-average interest rate (as a percent)	3.00%
Payments under long-term debt obligations
Due in one year or less	16,728
Due after one year through two years	12,741
Due after two years through three years	1,586
Total payments	31,055
Less amounts representing interest	913
Long-term debt	30,142	37,756
Capital lease obligations
Long-term debt obligations
Long-term debt	13,834	23,229
Weighted-average interest rate (as a percent)	4.40%
Payments under long-term debt obligations
Due in one year or less	8,897
Due after one year through two years	2,497
Due after two years through three years	2,433
Due after three years through four years	216
Due after four years through five years	222
Due after five years	365
Total payments	14,630
Less amounts representing interest	796
Long-term debt	$ 13,834	$ 23,229