LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Assets held under capital leases or securitized by notes payable
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	$ 1,080,962	$ 1,079,320
Less accumulated amortization	653,862	635,292
TOTAL PROPERTY, PLANT AND EQUIPMENT, NET	427,100	444,028
Assets held under capital leases or securitized by notes payable
Assets held under capital leases or securitized by notes payable
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	84,885	96,611
Less accumulated amortization	31,689	35,183
TOTAL PROPERTY, PLANT AND EQUIPMENT, NET	53,196	61,428
Land and structures (terminals) | Assets held under capital leases or securitized by notes payable
Assets held under capital leases or securitized by notes payable
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	1,794	1,794
Revenue equipment | Assets held under capital leases or securitized by notes payable
Assets held under capital leases or securitized by notes payable
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	81,588	93,004
Service, office, and other equipment | Assets held under capital leases or securitized by notes payable
Assets held under capital leases or securitized by notes payable
TOTAL PROPERTY, PLANT AND EQUIPMENT, GROSS	$ 1,503	$ 1,813