Note 8 - Troubled Debt Restructurings (Details) - Roll Forward of TDR Loans (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Financing Receivable, Modifications [Line Items]
Performing TDRs	$ 484,037		$ 474,070
Nonperforming TDRs	4,416		5,038
Beginning Balance [Member] | Residential Portfolio Segment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	834
Beginning Balance [Member] | Commercial [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	1,141
Beginning Balance [Member] | Commercial [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	2,355
Beginning Balance [Member] | Consumer [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	281
Beginning Balance [Member] | Consumer [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	51
Beginning Balance [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	1,422
Beginning Balance [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	3,240
Additions [Member] | Residential Portfolio Segment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[1]
Additions [Member] | Residential Portfolio Segment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[1]
Additions [Member] | Commercial [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[1]
Additions [Member] | Commercial [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[1]
Additions [Member] | Consumer [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[1]
Additions [Member] | Consumer [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[1]
Additions [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[1]
Additions [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[1]
Charge-offs [Member] | Residential Portfolio Segment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[2]
Charge-offs [Member] | Residential Portfolio Segment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[2]
Charge-offs [Member] | Commercial [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[2]
Charge-offs [Member] | Commercial [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[2]
Charge-offs [Member] | Consumer [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[2]
Charge-offs [Member] | Consumer [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[2]
Charge-offs [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[2]
Charge-offs [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[2]
Other Restructure [Member] | Residential Portfolio Segment [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs		[3]
Other Restructure [Member] | Residential Portfolio Segment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	(7)	[4]
Other Restructure [Member] | Commercial [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	(15)	[3]
Other Restructure [Member] | Commercial [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	(833)	[4]
Other Restructure [Member] | Consumer [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	(51)	[3]
Other Restructure [Member] | Consumer [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs		[4]
Other Restructure [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	(66)	[3]
Other Restructure [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	(840)	[4]
Ending Balance [Member] | Residential Portfolio Segment [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	827
Ending Balance [Member] | Commercial [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	1,126
Ending Balance [Member] | Commercial [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	1,522
Ending Balance [Member] | Consumer [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	230
Ending Balance [Member] | Consumer [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	51
Ending Balance [Member] | Performing Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Performing TDRs	1,356
Ending Balance [Member] | Nonperforming Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Nonperforming TDRs	$ 2,400

[1] Includes new TDRs and increases to existing TDRs.

[2] Post modification charge-offs.

[3] Includes principal payments, paydowns and performing loans previously restructured at market rates that are no longer reported as TDRs.

[4] Includes principal payments, paydowns and loans previously designated as non-performing that are currently performing in compliance with their modified terms.