Note 13 - Segment Information - Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets	$ 4,465,349	$ 3,950,727
Operating Segments [Member] | JBI [Member]
Assets	2,108,000	2,032,000
Operating Segments [Member] | DCS [Member]
Assets	1,182,000	951,000
Operating Segments [Member] | ICS [Member]
Assets	204,000	136,000
Operating Segments [Member] | JBT [Member]
Assets	283,000	279,000
Corporate and Reconciling Items [Member]
Assets	$ 688,000	$ 553,000