Note 4 - Loans and Allowance for Loan Losses (Details) - Impaired Loans, Net of Government Guarantees and Excluding Loans Acquired, Segregated by Class of Loans (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consumer:
Unpaid Contractual Principal Balance	$ 16,236,000	$ 20,185,000
Recorded Investment With No Allowance	14,247,000	13,071,000
Recorded Investment With Allowance	422,000	5,245,000
Total Recorded Investment	14,669,000	18,316,000
Related Allowance	2,065,000	1,960,000
Average Investment in Impaired Loans	17,482,000	21,579,000	34,800,000
Interest Income Recognized	764,000	882,000	1,800,000
Credit Cards [Member]
Consumer:
Unpaid Contractual Principal Balance	197,000	520,000
Recorded Investment With No Allowance	197,000	520,000
Total Recorded Investment	197,000	520,000
Related Allowance	6,000	16,000
Average Investment in Impaired Loans	425,000	518,000
Interest Income Recognized	20,000	15,000
Other Consumer [Member]
Consumer:
Unpaid Contractual Principal Balance	604,000	925,000
Recorded Investment With No Allowance	610,000	878,000
Recorded Investment With Allowance	9,000	32,000
Total Recorded Investment	619,000	910,000
Related Allowance	118,000	171,000
Average Investment in Impaired Loans	780,000	993,000
Interest Income Recognized	34,000	41,000
Total Consumer Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	801,000	1,445,000
Recorded Investment With No Allowance	807,000	1,398,000
Recorded Investment With Allowance	9,000	32,000
Total Recorded Investment	816,000	1,430,000
Related Allowance	124,000	187,000
Average Investment in Impaired Loans	1,205,000	1,511,000
Interest Income Recognized	54,000	56,000
Construction Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	7,400,000	3,251,000
Recorded Investment With No Allowance	7,020,000	2,036,000
Recorded Investment With Allowance		1,171,000
Total Recorded Investment	7,020,000	3,207,000
Related Allowance	599,000	371,000
Average Investment in Impaired Loans	4,334,000	3,692,000
Interest Income Recognized	189,000	152,000
Single Family Residential Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	4,442,000	4,497,000
Recorded Investment With No Allowance	3,948,000	2,306,000
Recorded Investment With Allowance	377,000	1,645,000
Total Recorded Investment	4,325,000	3,951,000
Related Allowance	899,000	745,000
Average Investment in Impaired Loans	4,291,000	3,754,000
Interest Income Recognized	187,000	155,000
Other Commercial Real Estate Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	1,955,000	10,328,000
Recorded Investment With No Allowance	1,446,000	6,868,000
Recorded Investment With Allowance	36,000	2,319,000
Total Recorded Investment	1,482,000	9,187,000
Related Allowance	268,000	564,000
Average Investment in Impaired Loans	6,789,000	11,924,000
Interest Income Recognized	296,000	491,000
Total Real Estate Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	13,797,000	18,076,000
Recorded Investment With No Allowance	12,414,000	11,210,000
Recorded Investment With Allowance	413,000	5,135,000
Total Recorded Investment	12,827,000	16,345,000
Related Allowance	1,756,000	1,680,000
Average Investment in Impaired Loans	15,413,000	19,370,000
Interest Income Recognized	672,000	798,000
Commercial [Member]
Consumer:
Unpaid Contractual Principal Balance	1,227,000	547,000
Recorded Investment With No Allowance	566,000	383,000
Recorded Investment With Allowance		78,000
Total Recorded Investment	566,000	461,000
Related Allowance	102,000	80,000
Average Investment in Impaired Loans	630,000	613,000
Interest Income Recognized	27,000	25,000
Agricultural Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	501,000	117,000
Recorded Investment With No Allowance	460,000	80,000
Total Recorded Investment	460,000	80,000
Related Allowance	83,000	13,000
Average Investment in Impaired Loans	234,000	85,000
Interest Income Recognized	10,000	3,000
Total Commercial Loans [Member]
Consumer:
Unpaid Contractual Principal Balance	1,728,000	664,000
Recorded Investment With No Allowance	1,026,000	463,000
Recorded Investment With Allowance		78,000
Total Recorded Investment	1,026,000	541,000
Related Allowance	185,000	93,000
Average Investment in Impaired Loans	864,000	698,000
Interest Income Recognized	$ 38,000	$ 28,000

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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