Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings - Non Accruing Troubled Debt Restructuring [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	$ 41,806	$ 42,595	$ 41,618	$ 34,162	$ 43,605	$ 38,769
Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	14,372		18,366
Rate Reduction and Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	27,434		22,392
Rate Reduction [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs			860
Commercial Portfolio Segment [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	2,338		3,552
Commercial Portfolio Segment [Member] | Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	2,248		1,423
Commercial Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	90		1,269
Commercial Portfolio Segment [Member] | Rate Reduction [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs			860
Real Estate Construction Portfolio Segment [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	16,079		19,462
Real Estate Construction Portfolio Segment [Member] | Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	10,172
Real Estate Construction Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	5,907		19,462
Commercial Real Estate Portfolio Segment [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	22,280		16,890
Commercial Real Estate Portfolio Segment [Member] | Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	1,555		15,917
Commercial Real Estate Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	20,725		973
Residential Portfolio Segment [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	1,109		1,714
Residential Portfolio Segment [Member] | Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	397		1,026
Residential Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Note 8 - Loans (Details) - Non-accrual Troubled Debt Restructurings [Line Items]
Non-accrual TDRs	$ 712		$ 688