Note 11 - Federal Income Taxes (Details) - Significant Components of Deferred Tax Assets and Liabilities (USD $)	Dec. 31, 2014	Dec. 31, 2013
Deferred income tax assets
Allowance for loan losses	$ 7,014,000	$ 7,987,000
Tax credit carryforwards	3,395,000	1,397,000
Nonaccrual loan interest income	471,000	605,000
Deferred compensation	1,304,000	567,000
Deferred loan fees	445,000us-gaap_DeferredTaxAssetsDeferredIncome	273,000us-gaap_DeferredTaxAssetsDeferredIncome
Fair value write-downs on foreclosed properties	212,000	241,000
Fair value of interest rate swap	89,000	92,000
Losses on capital investments	450,000	0
Stock compensation	521,000	207,000
Net operating loss carryforward	0	4,050,000
Unrealized loss on securities	0	2,908,000
Other	725,000us-gaap_DeferredTaxAssetsOther	136,000us-gaap_DeferredTaxAssetsOther
	14,626,000us-gaap_DeferredTaxAssetsGross	18,463,000us-gaap_DeferredTaxAssetsGross
Deferred income tax liabilities
Depreciation	1,217,000	419,000
Prepaid expenses	425,000	192,000
Core deposit intangible	5,386,000	0
Mortgage loan servicing rights	2,349,000	0
Unrealized gain on securities	112,000	0
Other	476,000us-gaap_DeferredTaxLiabilitiesOther	98,000us-gaap_DeferredTaxLiabilitiesOther
	9,965,000us-gaap_DeferredIncomeTaxLiabilities	709,000us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset before valuation allowance	4,661,000	17,754,000
Valuation allowance	(450,000)	0
Total net deferred tax asset	$ 4,211,000us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 17,754,000us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from mortgage servicing rights.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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