Note 14 - Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Commitments to Extend, Notional Amount	$ 1,971,848	$ 2,071,766
Commitments to Fund Fixed Rate Loans	87,300
Commitments to Fund Adjustable Rate Loans	$ 1,900,000
Operating Lease, Lease Term Minimum	1 year
Operating Lease, Lease Term Maximum	25 years
Operating Leases, Rent Expense	$ 9,300	8,200	$ 7,700
Operating Leases, Income Statement, Sublease Revenue	$ 300	$ 200	$ 300