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Note 10 - Federal Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Allowance for loan losses | $ 7,973,000 | $ 5,017,000
Deferred compensation | 511,000 | 577,000
Stock compensation | 541,000 | 720,000
Nonaccrual loan interest income | 211,000 | 239,000
Deferred loan fees | 924,000 | 104,000
Deferred Tax Assets, Capital Loss Carryforwards | 0 | 94,000
Fair value write-downs on foreclosed properties | 537,000 | 26,000
Other | 938,000 | 683,000
Deferred tax asset before valuation allowance | 11,635,000 | 7,460,000
Valuation allowance | 0 | (94,000)
Deferred tax asset after valuation allowance | 11,635,000 | 7,366,000
Depreciation | 1,175,000 | 1,743,000
Prepaid expenses | 297,000 | 269,000
Core deposit intangible | 498,000 | 787,000
Mortgage loan servicing rights | 1,720,000 | 977,000
Unrealized gain on securities | 1,458,000 | 982,000
Business combination adjustments | 2,142,000 | 2,058,000
Other | 521,000 | 485,000
Deferred tax liability | 7,811,000 | 7,301,000
Total net deferred tax asset | $ 3,824,000 | $ 65,000

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