Note 7 - Loans (Details) - Allowance for Loan Losses by Portfolio Segment (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision/(credit) for possible credit losses			$ 1,693	$ (675)
Commercial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	63,239	64,379	65,103	66,101
Provision/(credit) for possible credit losses	(10,839)	2,121	(12,067)	3,200
Charge-offs	(252)	(200)	(7,592)	(4,580)
Recoveries	4,148	436	10,852	2,015
Net (charge-offs)/recoveries	3,896	236	3,260	(2,565)
Balance	56,296	66,736	56,296	66,736
Reserve for impaired loans	2,730	10,849	2,730	10,849
Reserve for non-impaired loans	53,566	55,887	53,566	55,887
Reserve for off-balance sheet credit commitments	901	953	901	953
Real Estate Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	9,555	13,755	11,999	23,017
Provision/(credit) for possible credit losses	25,116	1,660	24,460	(8,622)
Charge-offs			(1,813)
Recoveries	32	1,236	57	2,256
Net (charge-offs)/recoveries	32	1,236	(1,756)	2,256
Balance	34,703	16,651	34,703	16,651
Reserve for impaired loans	2,604	5,691	2,604	5,691
Reserve for non-impaired loans	32,099	10,960	32,099	10,960
Reserve for off-balance sheet credit commitments	668	287	668	287
Commercial Mortgage Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	83,395	89,678	84,753	82,473
Provision/(credit) for possible credit losses	(17,950)	(5,710)	(20,991)	935
Charge-offs	(903)	(394)	(3,327)	(3,425)
Recoveries	2,197	2,514	6,304	6,105
Net (charge-offs)/recoveries	1,294	2,120	2,977	2,680
Balance	66,739	86,088	66,739	86,088
Reserve for impaired loans	7,999	6,129	7,999	6,129
Reserve for non-impaired loans	58,740	79,959	58,740	79,959
Reserve for off-balance sheet credit commitments	410	799	410	799
Residential Mortgage And Equity Lines Member
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	12,870	11,892	12,005	11,703
Provision/(credit) for possible credit losses	(1,427)	52	(562)	780
Charge-offs		(160)		(766)
Recoveries		158		225
Net (charge-offs)/recoveries		(2)		(541)
Balance	11,443	11,942	11,443	11,942
Reserve for impaired loans	481	693	481	693
Reserve for non-impaired loans	10,962	11,249	10,962	11,249
Reserve for off-balance sheet credit commitments	39	34	39	34
Installment And Other Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	18	29	29	28
Provision/(credit) for possible credit losses	(1)	6	(12)	(4)
Recoveries				11
Net (charge-offs)/recoveries				11
Balance	17	35	17	35
Reserve for impaired loans	0		0
Reserve for non-impaired loans	17	35	17	35
Reserve for off-balance sheet credit commitments		1		1
Total [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance	169,077	179,733	173,889	183,322
Provision/(credit) for possible credit losses	(5,101)	(1,871)	(9,172)	(3,711)
Charge-offs	(1,155)	(754)	(12,732)	(8,771)
Recoveries	6,377	4,344	17,213	10,612
Net (charge-offs)/recoveries	5,222	3,590	4,481	1,841
Balance	169,198	181,452	169,198	181,452
Reserve for impaired loans	13,814	23,362	13,814	23,362
Reserve for non-impaired loans	155,384	158,090	155,384	158,090
Reserve for off-balance sheet credit commitments	$ 2,018	$ 2,074	$ 2,018	$ 2,074