LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Assets Sec) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Arrangements
Total assets securing notes payable or held under capital leases	$ 138,492	$ 90,640
Less accumulated depreciation and amortization	25,120	26,305
Net assets securing notes payable or held under capital leases	113,372	64,335
Revenue equipment
Financing Arrangements
Total assets securing notes payable or held under capital leases	136,698	88,591
Land and structures (terminals)
Financing Arrangements
Total assets securing notes payable or held under capital leases	$ 1,794	1,794
Service, office, and other equipment
Financing Arrangements
Total assets securing notes payable or held under capital leases		$ 255