Note 4 - Loans and Allowance for Loan Losses (Details) - Troubled debt restructurings, excluding loans acquired, segregated by class of loans: (USD $) In Thousands, unless otherwise specified	9 Months Ended		12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended				9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Consumer [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Consumer [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Consumer Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Consumer Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Construction Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Construction Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Single Family Residential Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Single Family Residential Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Commercial Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Commercial Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Other Commercial Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Agricultural Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Agricultural Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member] Commercial Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Accruing TDR Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Other Consumer [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Consumer Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Construction Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Single Family Residential Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Single Family Residential Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Other Commercial Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Other Commercial Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Other Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Other Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Agricultural Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member] Commercial Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Nonaccrual TDR Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Other Consumer [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Other Consumer [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Consumer Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Consumer Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Construction Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Construction Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Single Family Residential Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Single Family Residential Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Other Commercial Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Other Commercial Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Real Estate Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Real Estate Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Other Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Other Commercial Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Agricultural Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Agricultural Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member] Commercial Loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member] Commercial Loans [Member]	Sep. 30, 2013 Loans, excluding acquired loans [Member]	Dec. 31, 2012 Loans, excluding acquired loans [Member]
Consumer:
Number of TDR loans	6	1	1	1	1	1	2	4	3	12	14	17	19	1	1	1	1	2	2	20	22	1	1	0	1	1	1	4	2	5	1	1	0	1	1	3	7	1	2	1	2	1	2	5	4	13	18	19	24	2	2	1	1	3	3	23	29
Balance on TDR loans (in Dollars)		$ 33	$ 33	$ 33	$ 33	$ 988	$ 1,212	$ 874	$ 570	$ 7,012	$ 8,508	$ 8,874	$ 10,290	$ 39	$ 39	$ 638	$ 653	$ 677	$ 692	$ 9,584	$ 11,015	$ 12	$ 12	$ 0	$ 8	$ 15	$ 608	$ 2,962	$ 616	$ 2,977	$ 85	$ 85	$ 0	$ 85	$ 85	$ 701	$ 3,074	$ 33	$ 45	$ 33	$ 45	$ 988	$ 1,212	$ 882	$ 585	$ 7,619	$ 11,470	$ 9,489	$ 13,267	$ 124	$ 124	$ 638	$ 653	$ 762	$ 777	$ 10,284	$ 14,089