LEGAL PROCEEDINGS, ENVIRONMENTAL MATTERS, AND OTHER EVENTS (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014 Underground fuel storage tanks state tank	Sep. 30, 2014 Clean Water Act Freight Transportation (ABF Freight)	Sep. 30, 2014 Environmental cleanup costs	Dec. 31, 2013 Environmental cleanup costs
Environmental Matters
Number of underground tanks where the company's subsidiaries store fuel for use in tractors and trucks	64
Number of states in which underground tanks are located	20
Reserve for environmental contingencies		$ 0	$ 0.9	$ 0.9