OPERATING SEGMENT DATA (BalSh) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
OPERATING SEGMENT DATA
ASSETS	$ 1,262,909	$ 1,127,622	$ 1,017,326
CAPITAL EXPENDITURES, GROSS	159,017	90,808	26,405
DEPRECIATION AND AMORTIZATION EXPENSE	93,042	86,222	88,389
Assets acquired through notes payable and capital leases	80,592	55,325	36
Amortization of intangibles	4,002	4,352	4,174
Operating Segments | Freight Transportation (ABF Freight)
OPERATING SEGMENT DATA
ASSETS	694,059	621,734	530,678
CAPITAL EXPENDITURES, GROSS	122,542	78,766	11,091
DEPRECIATION AND AMORTIZATION EXPENSE	74,765	68,752	72,971
Assets acquired through notes payable and capital leases	80,600	55,300
Operating Segments | Premium Logistics (Panther)
OPERATING SEGMENT DATA
ASSETS	216,075	218,135	216,747
CAPITAL EXPENDITURES, GROSS	23,275	6,414	3,854
DEPRECIATION AND AMORTIZATION EXPENSE	11,436	11,362	10,516
Amortization of intangibles	3,600	4,200	4,200
Operating Segments | Transportation Management (ABF Logistics)
OPERATING SEGMENT DATA
ASSETS	75,023	37,571	27,836
CAPITAL EXPENDITURES, GROSS	241	158	286
DEPRECIATION AND AMORTIZATION EXPENSE	1,138	1,006	640
Amortization of intangibles	100
Operating Segments | Emergency & Preventative Maintenance (FleetNet)
OPERATING SEGMENT DATA
ASSETS	21,958	23,532	21,517
CAPITAL EXPENDITURES, GROSS	1,007	550	1,314
DEPRECIATION AND AMORTIZATION EXPENSE	1,119	961	540
Amortization of intangibles	300	200
Operating Segments | Household Goods Moving Services (ABF Moving)
OPERATING SEGMENT DATA
ASSETS	28,547	22,276	20,941
CAPITAL EXPENDITURES, GROSS	703	424	493
DEPRECIATION AND AMORTIZATION EXPENSE	1,186	1,384	1,247
Operating Segments | Maximum | Freight Transportation (ABF Freight)
OPERATING SEGMENT DATA
Assets acquired through notes payable and capital leases			100
Other and eliminations
OPERATING SEGMENT DATA
ASSETS	227,247	204,374	199,607
CAPITAL EXPENDITURES, GROSS	11,249	4,496	9,367
DEPRECIATION AND AMORTIZATION EXPENSE	$ 3,398	$ 2,757	$ 2,475