Note 14 - Commitments and Contingencies (Details) - Financial Instruments With Off-balance Sheet Risk - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments	$ 2,059,514	$ 2,173,927
Commitments to Extend Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments	1,971,848	2,071,766
Standby Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments	49,081	53,910
Commercial Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments	38,131	48,143
Bill of Lading Guarantees [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments	$ 454	$ 108