Note 13 - Segment Information - Operating Revenues (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues	$ 1,990,160	$ 1,843,334	$ 1,726,915	$ 1,629,158	$ 1,721,062	$ 1,690,659	$ 1,615,026	$ 1,528,712	$ 7,189,568	$ 6,555,459	$ 6,187,646
Operating Segments [Member]
Revenues									7,206,000	6,569,000	6,201,000
Operating Segments [Member] | JBI [Member]
Revenues									4,084,000	3,796,000	3,665,000
Operating Segments [Member] | DCS [Member]
Revenues									1,719,000	1,533,000	1,451,000
Operating Segments [Member] | ICS [Member]
Revenues									1,025,000	852,000	699,000
Operating Segments [Member] | JBT [Member]
Revenues									378,000	388,000	386,000
Intersegment Eliminations [Member]
Revenues									$ (16,000)	$ (14,000)	$ (13,000)