Note 10 - Business Segments - Depreciation and Amortization (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Depreciation and amortization	$ 130,298	$ 123,995	$ 260,393	$ 243,924
Segment Reconciling Items [Member]
Depreciation and amortization	10,800	8,400	21,500	16,900
JBI [Member] | Operating Segments [Member]
Depreciation and amortization	46,800	44,800	93,200	89,100
DCS [Member] | Operating Segments [Member]
Depreciation and amortization	55,600	53,500	111,900	104,500
ICS [Member] | Operating Segments [Member]
Depreciation and amortization	300	900	600	1,800
FMS [Member] | Operating Segments [Member]
Depreciation and amortization	8,200	8,000	16,400	14,400
JBT [Member] | Operating Segments [Member]
Depreciation and amortization	$ 8,600	$ 8,400	$ 16,800	$ 17,200