LONG-TERM DEBT AND FINANCING ARRANGEMENTS (Assets Sec) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Arrangements
Total assets securing notes payable or held under finance leases	$ 304,984	$ 293,799
Less accumulated depreciation and amortization	91,811	71,405
Net assets securing notes payable or held under finance leases	213,173	222,394
Revenue equipment
Financing Arrangements
Total assets securing notes payable or held under finance leases	276,574	265,315
Software
Financing Arrangements
Total assets securing notes payable or held under finance leases	2,140	2,140
Service, office, and other equipment
Financing Arrangements
Total assets securing notes payable or held under finance leases	$ 26,270	$ 26,344