Note 6 - Loans (Details) - Allowance for Credit Losses and Recorded Investment in Financing Receivables - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
ALLL:
Beginning balance	$ 11,402	$ 9,882	$ 10,820	$ 14,172
Charge offs	(779)	(585)	(1,669)	(6,944)
Recoveries	268	53	1,740	672
Provision		1,050		2,500
Ending balance	10,891	10,400	10,891	10,400
ALLL:
Allowance for credit losses: individually evaluated for impairment	789		789		$ 1,556
Allowance for credit losses: collectively evaluated for impairment	10,102		10,102		9,264
Gross loans:
Financing receivables: individually evaluated for impairment	22,905		22,905		31,408
Allowance for credit losses: collectively evaluated for impairment	695,628		695,628		629,490
Gross loans	718,533		718,533		660,898
Commercial Portfolio Segment [Member]
ALLL:
Beginning balance	3,389	3,331	3,503	7,057
Charge offs		(299)	(406)	(4,105)
Recoveries	121	43	869	500
Provision	(91)	364	(547)	(13)
Ending balance	3,419	3,439	3,419	3,439
ALLL:
Allowance for credit losses: individually evaluated for impairment	134		134		314
Allowance for credit losses: collectively evaluated for impairment	3,285		3,285		3,189
Gross loans:
Financing receivables: individually evaluated for impairment	2,562		2,562		6,597
Allowance for credit losses: collectively evaluated for impairment	142,187		142,187		143,656
Gross loans	144,749		144,749		150,253
Commercial Real Estate Portfolio Segment [Member]
ALLL:
Beginning balance	5,447	3,870	4,875	2,784
Charge offs	(289)	(241)	(428)	(2,525)
Recoveries	1	1	669	1
Provision	64	625	107	3,995
Ending balance	5,223	4,255	5,223	4,255
ALLL:
Allowance for credit losses: individually evaluated for impairment	59		59		432
Allowance for credit losses: collectively evaluated for impairment	5,164		5,164		4,443
Gross loans:
Financing receivables: individually evaluated for impairment	8,262		8,262		11,753
Allowance for credit losses: collectively evaluated for impairment	410,798		410,798		352,553
Gross loans	419,060		419,060		364,306
Residential Portfolio Segment [Member]
ALLL:
Beginning balance	1,480	2,333	1,671	2,493
Charge offs	(309)	(44)	(450)	(313)
Recoveries	139	9	202	171
Provision	(45)	(95)	(158)	(148)
Ending balance	1,265	2,203	1,265	2,203
ALLL:
Allowance for credit losses: individually evaluated for impairment	583		583		795
Allowance for credit losses: collectively evaluated for impairment	682		682		875
Gross loans:
Financing receivables: individually evaluated for impairment	12,048		12,048		13,023
Allowance for credit losses: collectively evaluated for impairment	96,032		96,032		97,944
Gross loans	108,080		108,080		110,967
Consumer Portfolio Segment [Member]
ALLL:
Beginning balance	583	238	449	35
Charge offs	(181)	(1)	(385)	(1)
Recoveries	7
Provision	194	124	539	327
Ending balance	603	361	603	361
ALLL:
Allowance for credit losses: individually evaluated for impairment	13		13		15
Allowance for credit losses: collectively evaluated for impairment	590		590		435
Gross loans:
Financing receivables: individually evaluated for impairment	33		33		35
Allowance for credit losses: collectively evaluated for impairment	46,611		46,611		35,337
Gross loans	46,644		46,644		35,372
Unallocated Financing Receivables [Member]
ALLL:
Beginning balance	503	110	322	1,803
Provision	(122)	32	59	(1,661)
Ending balance	381	$ 142	381	$ 142
ALLL:
Allowance for credit losses: collectively evaluated for impairment	$ 381		$ 381		$ 322