Note 7 - Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		18 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016
Commercial Portfolio Segment [Member]
Balance	$ 56,381	$ 49,705	$ 56,199	$ 47,501
Provision/(credit) for possible credit losses	170	184	1,435	1,005
Charge-offs	(6,688)	(2,580)	(8,758)	(3,444)
Recoveries	727	231	1,714	2,478
Net (charge-offs)/recoveries	(5,961)	(2,349)	(7,044)	(966)
Balance	50,590	47,540	50,590	47,540	$ 50,590
Charge-offs	(6,688)	(2,580)	(8,758)	(3,444)
Recoveries	727	231	1,714	2,478
Reserve for impaired loans	1,395	966	1,395	966	1,395
Reserve for non-impaired loans	49,195	46,574	49,195	46,574	49,195
Reserve for off-balance sheet credit commitments	1,969	942	1,969	942	1,969
Real Estate Construction Portfolio Segment [Member]
Balance	12,744	23,270	22,170	27,652
Provision/(credit) for possible credit losses	(2,038)	2,982	(18,740)	(1,470)
Charge-offs
Recoveries	47	52	7,323	122
Net (charge-offs)/recoveries	47	52	7,323	122
Balance	10,753	26,304	10,753	26,304	10,753
Charge-offs
Recoveries	47	52	7,323	122
Reserve for impaired loans
Reserve for non-impaired loans	10,753	26,304	10,753	26,304	10,753
Reserve for off-balance sheet credit commitments		427		427
Commercial Real Estate Portfolio Segment [Member]
Balance	50,451	71,318	49,440	74,673
Provision/(credit) for possible credit losses	(3,815)	(5,880)	(2,837)	(7,580)
Charge-offs	(945)	(65)	(1,055)	(3,516)
Recoveries	399	1,872	542	3,668
Net (charge-offs)/recoveries	(546)	1,807	(513)	152
Balance	46,090	67,245	46,090	67,245	46,090
Charge-offs	(945)	(65)	(1,055)	(3,516)
Recoveries	399	1,872	542	3,668
Reserve for impaired loans	5,891	6,554	5,891	6,554	5,891
Reserve for non-impaired loans	40,199	60,691	40,199	60,691	40,199
Reserve for off-balance sheet credit commitments	34	163	34	163	34
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Balance	14,969	11,777	11,145	11,578
Provision/(credit) for possible credit losses	528	559	4,488	886
Charge-offs		(13)	(148)	(161)
Recoveries	6		18	20
Net (charge-offs)/recoveries	6	(13)	(130)	(141)
Balance	15,503	12,323	15,503	12,323	15,503
Charge-offs		(13)	(148)	(161)
Recoveries	6		18	20
Reserve for impaired loans	438	464	438	464	438
Reserve for non-impaired loans	15,065	11,859	15,065	11,859	15,065
Reserve for off-balance sheet credit commitments	119	42	119	42	119
Consumer Portfolio Segment [Member]
Balance	7	19	9	16
Provision/(credit) for possible credit losses	5	5	3	9
Charge-offs
Recoveries		1
Net (charge-offs)/recoveries		1
Balance	12	25	12	25	12
Charge-offs
Recoveries		1
Reserve for impaired loans
Reserve for non-impaired loans	12	25	12	25	12
Reserve for off-balance sheet credit commitments	2		2		2
Balance	134,552	156,089	138,963	161,420
Provision/(credit) for possible credit losses	(5,150)	(2,150)	(15,651)	(7,150)
Charge-offs	(7,633)	(2,658)	(9,961)	(7,121)
Recoveries	1,179	2,156		6,288	9,597
Net (charge-offs)/recoveries	(6,454)	(502)	(364)	(833)
Balance	122,948	153,437	122,948	153,437	122,948
Charge-offs	(7,633)	(2,658)	(9,961)	(7,121)
Recoveries	1,179	2,156		6,288	9,597
Reserve for impaired loans	7,724	7,984	7,724	7,984	7,724
Reserve for non-impaired loans	115,224	145,453	115,224	145,453	115,224
Reserve for off-balance sheet credit commitments	$ 2,124	$ 1,574	$ 2,124	$ 1,574	$ 2,124