Note 5 - Loans and Allowance for Credit Losses (Details) - Allowance for Credit Losses by Portfolio Segment (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	$ 40,921	$ 37,492
Loans charged-off	(6,934)	(7,039)
Recoveries of loans previously charged-off	1,209	866
Net loan charged-off	(5,725)	(6,173)
Provision for credit losses	10,879us-gaap_ProvisionForLoanAndLeaseLosses	9,602us-gaap_ProvisionForLoanAndLeaseLosses
Ending balance	46,075	40,921
For the Year Ended December 31, 2014
Individually evaluated for impairment	8,064	6,520
Collectively evaluated for impairment	38,011	34,401
Ending balance	46,075	40,921
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	9,780	9,412
Loans charged-off	(2,634)	(4,275)
Recoveries of loans previously charged-off	977	161
Net loan charged-off	(1,657)	(4,114)
Provision for credit losses	5,099	4,482
Ending balance	13,222	9,780
For the Year Ended December 31, 2014
Individually evaluated for impairment	5,334	1,323
Collectively evaluated for impairment	7,888	8,457
Ending balance	13,222	9,780
Commercial Real Estate Investment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	10,359	9,148
Loans charged-off	(121)	(602)
Recoveries of loans previously charged-off	42
Net loan charged-off	(79)	(602)
Provision for credit losses	1,162	1,813
Ending balance	11,442	10,359
For the Year Ended December 31, 2014
Individually evaluated for impairment	751	1,098
Collectively evaluated for impairment	10,691	9,261
Ending balance	11,442	10,359
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	3,899	2,781
Loans charged-off	(752)
Recoveries of loans previously charged-off	7
Net loan charged-off	(745)
Provision for credit losses	(200)	1,118
Ending balance	2,954	3,899
For the Year Ended December 31, 2014
Individually evaluated for impairment	577	1,853
Collectively evaluated for impairment	2,377	2,046
Ending balance	2,954	3,899
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	944	659
Loans charged-off	(138)
Net loan charged-off	(138)
Provision for credit losses	453	285
Ending balance	1,259	944
For the Year Ended December 31, 2014
Individually evaluated for impairment		27
Collectively evaluated for impairment	1,259	917
Ending balance	1,259	944
Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	1,871	1,730
Loans charged-off	(379)	(89)
Recoveries of loans previously charged-off	10	11
Net loan charged-off	(369)	(78)
Provision for credit losses	(33)	219
Ending balance	1,469	1,871
For the Year Ended December 31, 2014
Individually evaluated for impairment	430	526
Collectively evaluated for impairment	1,039	1,345
Ending balance	1,469	1,871
Consumer, Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	134	371
Loans charged-off	(189)	(63)
Recoveries of loans previously charged-off	90	6
Net loan charged-off	(99)	(57)
Provision for credit losses	69	(180)
Ending balance	104	134
For the Year Ended December 31, 2014
Individually evaluated for impairment	45	68
Collectively evaluated for impairment	59	66
Ending balance	104	134
Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	13,934	13,391
Loans charged-off	(2,721)	(2,010)
Recoveries of loans previously charged-off	83	688
Net loan charged-off	(2,638)	(1,322)
Provision for credit losses	4,329	1,865
Ending balance	15,625	13,934
For the Year Ended December 31, 2014
Individually evaluated for impairment	927	1,625
Collectively evaluated for impairment	14,698	12,309
Ending balance	$ 15,625	$ 13,934

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Amount of other addition (reduction) in allowance reserve for credit loss.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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