Note 4 - Loans and Allowance for Loan Losses (Details) - Age Analysis of Past Due Loans, Excluding Loans Acquired, Segregated by Class of Loans (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Consumer:
Total Loans	$ 2,390,000	$ 2,400,000
Credit Cards [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	660	712
90 Days or More Past Due	424	520
Total Past Due	1,084	1,232
Current	175,155	183,703
Total Loans	176,239	184,935
90 Days Past Due & Accruing	197	230
Credit Cards [Member]
Consumer:
Total Loans	176,239	184,935
Student Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due		627
90 Days or More Past Due	323	2,264
Total Past Due	323	2,891
Current	75	23,015
Total Loans	398	25,906
90 Days Past Due & Accruing	323	2,264
Student Loans [Member]
Consumer:
Total Loans	398	25,906
Other Consumer [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	1,097	911
90 Days or More Past Due	426	458
Total Past Due	1,523	1,369
Current	104,472	97,482
Total Loans	105,998	98,851
90 Days Past Due & Accruing	102	185
Other Consumer [Member]
Consumer:
Total Loans	105,998	98,851
Consumer Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	1,757	2,250
90 Days or More Past Due	1,173	3,242
Total Past Due	2,930	5,492
Current	279,705	304,200
Total Loans	282,635	309,692
90 Days Past Due & Accruing	622	2,679
Consumer Loans [Member]
Consumer:
Total Loans	282,635	309,692
Construction Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	453	583
90 Days or More Past Due	28	30
Total Past Due	481	613
Current	162,931	145,845
Total Loans	163,412	146,458
Construction Loans [Member]
Consumer:
Total Loans	163,412	146,458
Single Family Residential Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	1,360	2,793
90 Days or More Past Due	642	1,114
Total Past Due	2,002	3,907
Current	415,185	388,378
Total Loans	417,187	392,285
90 Days Past Due & Accruing	172	94
Single Family Residential Loans [Member]
Consumer:
Total Loans	417,187	392,285
Other Commercial Real Estate Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	725
90 Days or More Past Due	1,063
Total Past Due	1,788
Current	651,946
Total Loans	653,734
Other Commercial Real Estate Loans [Member]
Consumer:
Total Loans	653,734	626,333
Real Estate Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	2,538	4,395
90 Days or More Past Due	1,733	2,677
Total Past Due	4,271	7,072
Current	1,230,062	1,158,004
Total Loans	1,234,333	1,165,076
90 Days Past Due & Accruing	172	176
Real Estate Loans [Member]
Consumer:
Total Loans	1,234,333	1,165,076
Commercial Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	573	357
90 Days or More Past Due	496	376
Total Past Due	1,069	733
Current	232,441	163,596
Total Loans	233,510	164,329
90 Days Past Due & Accruing	49	96
Commercial Loans [Member]
Consumer:
Total Loans	345,077	263,215
Agricultural Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	423	42
90 Days or More Past Due	507	37
Total Past Due	930	79
Current	110,637	98,807
Total Loans	111,567	98,886
90 Days Past Due & Accruing	237
Agricultural Loans [Member]
Consumer:
Total Loans	111,567	98,886
Total Commercial Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	996	399
90 Days or More Past Due	1,003	413
Total Past Due	1,999	812
Current	343,078	262,403
Total Loans	345,077	263,215
90 Days Past Due & Accruing	286	96
Other Commercial Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due		1,019
90 Days or More Past Due		1,533
Total Past Due		2,552
Current	6,797	623,781
Total Loans	6,797	626,333
90 Days Past Due & Accruing		82
Other Commercial Loans [Member]
Consumer:
Total Loans	233,510	164,329
Total Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Gross 30-89 Days Past Due	5,291	7,044
90 Days or More Past Due	3,909	6,332
Total Past Due	9,200	13,376
Current	1,859,642	1,729,262
Total Loans	1,868,842	1,742,638
90 Days Past Due & Accruing	1,080	2,951
Other Loans [Member] | Loans, excluding acquired loans [Member]
Consumer:
Current		4,655
Total Loans		4,655
Other Loans [Member]
Consumer:
Total Loans	$ 6,797	$ 4,655