Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	$ 36,991	$ 34,597	$ 49,998
Collectively evaluated for impairment	3,242,438	2,910,561	2,641,360
Ending balance	3,279,429	2,945,158	2,691,358
Commercial Loan [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	17,405	9,614	16,407
Collectively evaluated for impairment	709,206	684,736	620,216
Ending balance	726,611	694,350	636,623
Commercial Real Estate Investment [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	2,913	2,682	5,560
Collectively evaluated for impairment	1,299,566	1,117,118	998,163
Ending balance	1,302,479	1,119,800	1,003,723
Commercial Real Estate Owner Occupied [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	3,230	7,574	8,580
Collectively evaluated for impairment	326,843	309,917	302,755
Ending balance	330,073	317,491	311,335
Residential Mortgage [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment		113
Collectively evaluated for impairment	123,587	90,305	78,813
Ending balance	123,587	90,418	78,813
Home Equity Line of Credit [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	561	682	561
Collectively evaluated for impairment	108,370	109,560	108,004
Ending balance	108,931	110,242	108,565
Consumer, Other [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment		70	11
Collectively evaluated for impairment	7,116	3,961	7,970
Ending balance	7,116	4,031	7,981
Construction Loans [Member]
Note 6 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	12,882	13,862	18,879
Collectively evaluated for impairment	667,750	594,964	525,439
Ending balance	$ 680,632	$ 608,826	$ 544,318