Note 4 - Loans and Allowance for Credit Losses (Details) - Loans by Delinquency and Nonaccrual Status (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	$ 1,696,647		$ 1,785,530
30-59 Days Past Due and Accruing	10,888		15,595
60-89 Days Past Due and Accruing	6,128		4,907
Past Due 90 days or More and Accruing	418		410
Nonaccrual	18,301		21,302
Total Loans	1,732,382		1,827,744
Originated Loans [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	368,428		336,497
30-59 Days Past Due and Accruing	723		677
60-89 Days Past Due and Accruing	414		383
Nonaccrual	495		1,267
Total Loans	370,060		338,824
Originated Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	563,817		586,619
30-59 Days Past Due and Accruing	3,679		4,012
60-89 Days Past Due and Accruing	1,469		2,473
Nonaccrual	4,214		3,549
Total Loans	573,179		596,653
Originated Loans [Member] | Construction Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	8,894		10,275
60-89 Days Past Due and Accruing	930
Nonaccrual			448
Total Loans	9,824		10,723
Originated Loans [Member] | Residential Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	152,538		173,082
30-59 Days Past Due and Accruing	2,659		2,789
60-89 Days Past Due and Accruing	1,597		325
Total Loans	156,794		176,196
Originated Loans [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	375,971		396,725
30-59 Days Past Due and Accruing	2,936		3,035
60-89 Days Past Due and Accruing	459		606
Past Due 90 days or More and Accruing	342		410
Nonaccrual			112
Total Loans	379,708		400,888
Originated Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	1,469,648		1,503,198
30-59 Days Past Due and Accruing	9,997		10,513
60-89 Days Past Due and Accruing	4,869		3,787
Past Due 90 days or More and Accruing	342		410
Nonaccrual	4,709		5,376
Total Loans	1,489,565		1,523,284
Purchased Non-Covered Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	209,775		45,755
30-59 Days Past Due and Accruing	891		4,237
60-89 Days Past Due and Accruing	1,255		180
Past Due 90 days or More and Accruing	76
Nonaccrual	13,297		3,618
Total Loans	225,294		53,790
Purchased Covered Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current and Accruing	17,224		236,577
30-59 Days Past Due and Accruing			845
60-89 Days Past Due and Accruing	4		940
Nonaccrual	295		12,308
Total Loans	17,523	[1]	250,670	[1]
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	388,918		364,159
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	733,171		799,019
Construction Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	12,705		13,896
Residential Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	159,982		185,057
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	$ 437,606		$ 465,613

[1] Credit risk profile reflects internally assigned grade of purchased covered loans without regard to FDIC indemnification.