Note 5 - Loans (Details) - Accruing Troubled Debt Restructurings - Accruing Troubled Debt Restructuring [Member] - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Accruing TDRs	$ 81,680	$ 104,356
Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	30,200	41,196
Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	7,044	26,694
Rate Reduction and Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	44,436	36,056
Rate Reduction and Forgiveness of Principal [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs		410
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	10,024	16,506
Commercial Portfolio Segment [Member] | Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	8,298	11,572
Commercial Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	1,726	4,934
Real Estate Construction Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	5,696	5,765
Real Estate Construction Portfolio Segment [Member] | Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs		5,765
Real Estate Construction Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	5,696
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	56,546	73,588
Commercial Real Estate Portfolio Segment [Member] | Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	16,701	20,543
Commercial Real Estate Portfolio Segment [Member] | Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	6,045	26,694
Commercial Real Estate Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	33,800	26,351
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	9,414	8,497
Residential Portfolio Segment [Member] | Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	5,201	3,316
Residential Portfolio Segment [Member] | Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	999
Residential Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs	$ 3,214	4,771
Residential Portfolio Segment [Member] | Rate Reduction and Forgiveness of Principal [Member]
Financing Receivable, Modifications [Line Items]
Accruing TDRs		$ 410