Note 4 - Loans and Allowance for Loan Losses (Details) - Activity in Allowance for Loan Losses and the Recorded Investments in Loans (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Allowance for loan losses:
Provision for loan losses	$ (700,000)	$ (1,500,000)	$ (2,600,000)	$ (3,000,000)
Total loans:
Loans	2,073,482,000		2,073,482,000		1,053,243,000
Originated Loan [Member] | Commercial Portfolio Segment [Member]
Allowance for loan losses:
Allowance for loan losses	19,001,000	23,717,000	20,455,000	26,043,000
Allowance for loan losses: individually evaluated for impairment	9,440,000	13,806,000	9,440,000	13,806,000
Allowance for loan losses: collectively evaluated for impairment	9,667,000	8,576,000	9,667,000	8,576,000
Provision for loan losses	(334,000)	(1,480,000)	(1,788,000)	(2,644,000)
Charge-offs	(98,000)	(363,000)	(684,000)	(2,775,000)
Recoveries	538,000	508,000	1,124,000	1,758,000
Allowance for loan losses	19,107,000	22,382,000	19,107,000	22,382,000
Total loans:
Loans	1,076,609,000	985,616,000	1,076,609,000	985,616,000	986,696,000
Loans: individually evaluated for impairment	27,199,000	49,590,000	27,199,000	49,590,000
Loans: collectively evaluated for impairment	1,049,410,000	936,026,000	1,049,410,000	936,026,000
Originated Loan [Member] | Retail Loan [Member]
Allowance for loan losses:
Allowance for loan losses	1,957,000	2,302,000	2,358,000	2,645,000
Allowance for loan losses: individually evaluated for impairment	922,000	1,030,000	922,000	1,030,000
Allowance for loan losses: collectively evaluated for impairment	852,000	1,529,000	852,000	1,529,000
Provision for loan losses	(345,000)	(10,000)	(779,000)	(373,000)
Charge-offs	(5,000)	(19,000)	(7,000)	(22,000)
Recoveries	167,000	286,000	202,000	309,000
Allowance for loan losses	1,774,000	2,559,000	1,774,000	2,559,000
Total loans:
Loans	68,488,000	73,046,000	68,488,000	73,046,000	66,547,000
Loans: individually evaluated for impairment	3,405,000	4,087,000	3,405,000	4,087,000
Loans: collectively evaluated for impairment	65,083,000	68,959,000	65,083,000	68,959,000
Originated Loan [Member] | Unallocated Financing Receivables [Member]
Allowance for loan losses:
Allowance for loan losses	(4,000)	16,000	8,000	(11,000)
Allowance for loan losses: individually evaluated for impairment	0	0	0	0
Allowance for loan losses: collectively evaluated for impairment	(25,000)	6,000	(25,000)	6,000
Provision for loan losses	(21,000)	(10,000)	(33,000)	17,000
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Allowance for loan losses	(25,000)	6,000	(25,000)	6,000
Originated Loan [Member]
Allowance for loan losses:
Allowance for loan losses	20,954,000	26,035,000	22,821,000	28,677,000
Allowance for loan losses: individually evaluated for impairment	10,362,000	14,836,000	10,362,000	14,836,000
Allowance for loan losses: collectively evaluated for impairment	10,494,000	10,111,000	10,494,000	10,111,000
Provision for loan losses	(700,000)	(1,500,000)	(2,600,000)	(3,000,000)
Charge-offs	(103,000)	(382,000)	(691,000)	(2,797,000)
Recoveries	705,000	794,000	1,326,000	2,067,000
Allowance for loan losses	20,856,000	24,947,000	20,856,000	24,947,000
Total loans:
Loans	1,145,097,000	1,058,662,000	1,145,097,000	1,058,662,000	1,053,243,000
Loans: individually evaluated for impairment	30,604,000	53,677,000	30,604,000	53,677,000
Loans: collectively evaluated for impairment	1,114,493,000	1,004,985,000	1,114,493,000	1,004,985,000
Commercial Portfolio Segment [Member]
Total loans:
Loans	1,687,735,000		1,687,735,000		986,696,000
Retail Loan [Member]
Total loans:
Loans	$ 385,747,000		$ 385,747,000		$ 66,547,000