Note 13 - Commitments and Contingencies - Financial Instruments With Off-balance Sheet Risk (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Commitments	$ 2,174,995	$ 2,059,514
Commitments to Extend Credit [Member]
Commitments	2,062,241	1,971,848
Standby Letters of Credit [Member]
Commitments	75,396	49,081
Commercial Letters of Credit [Member]
Commitments	37,283	38,131
Bill of Lading Guarantees [Member]
Commitments	$ 75	$ 454