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Note 12 - Regulatory Matters - Actual Capital Amounts and Ratios (Details) $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Capital | $ 228,752 | $ 219,750
Capital to risk weighted assets | 0.154 | 0.143
Capital required for capital adequacy | $ 156,433 | $ 161,155
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Tier one risk based capital | $ 210,129 | $ 201,749
Tier one risk based capital to risk weighted assets | 0.141 | 0.131
Tier one risk based capital required for capital adequacy | $ 126,636 | $ 130,459
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one leverage capital | $ 210,129 | $ 201,749
Tier one leverage capital to average assets | 0.101 | 0.092
Tier one leverage capital required for capital adequacy | $ 83,528 | $ 87,421
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Common equity tier one capital | $ 210,129 | $ 201,749
Common equity tier one risk based capital to risk weighted assets | 0.141 | 0.131
Common equity tier one capital required for capital adequacy | $ 104,288 | $ 107,436
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Boone Bank and Trust [Member] |  |
Capital | $ 16,647 | $ 16,446
Capital to risk weighted assets | 0.135 | 0.135
Capital required for capital adequacy | $ 12,917 | $ 12,809
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 12,302 | $ 12,199
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 15,560 | $ 15,404
Tier one risk based capital to risk weighted assets | 0.126 | 0.126
Tier one risk based capital required for capital adequacy | $ 10,457 | $ 10,369
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 9,842 | $ 9,759
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 15,560 | $ 15,404
Tier one leverage capital to average assets | 0.095 | 0.091
Tier one leverage capital required for capital adequacy | $ 6,549 | $ 6,743
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 8,187 | $ 8,429
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 15,560 | $ 15,404
Common equity tier one risk based capital to risk weighted assets | 0.126 | 0.126
Common equity tier one capital required for capital adequacy | $ 8,612 | $ 8,540
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 7,996 | $ 7,930
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%
First National Bank [Member] | Also Conducts Business Out of 3 Full Service Offices in Des Moines Metro Area [Member] |  |
Capital | $ 115,343 | $ 112,663
Capital to risk weighted assets | 0.152 | 0.146
Capital required for capital adequacy | $ 79,781 | $ 81,211
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 75,982 | $ 77,344
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 105,844 | $ 103,707
Tier one risk based capital to risk weighted assets | 0.139 | 0.134
Tier one risk based capital required for capital adequacy | $ 64,585 | $ 65,742
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 60,786 | $ 61,875
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 105,844 | $ 103,707
Tier one leverage capital to average assets | 0.10 | 0.093
Tier one leverage capital required for capital adequacy | $ 42,171 | $ 44,595
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 52,713 | $ 55,744
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 105,844 | $ 103,707
Common equity tier one risk based capital to risk weighted assets | 0.139 | 0.134
Common equity tier one capital required for capital adequacy | $ 53,187 | $ 54,141
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 49,388 | $ 50,274
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%
Iowa State Savings Bank [Member] |  |
Capital | $ 27,713 | $ 27,161
Capital to risk weighted assets | 0.166 | 0.151
Capital required for capital adequacy | $ 17,483 | $ 18,866
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 16,650 | $ 17,967
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 25,629 | $ 24,915
Tier one risk based capital to risk weighted assets | 0.154 | 0.139
Tier one risk based capital required for capital adequacy | $ 14,153 | $ 15,272
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 13,320 | $ 14,374
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 25,629 | $ 24,915
Tier one leverage capital to average assets | 0.092 | 0.095
Tier one leverage capital required for capital adequacy | $ 11,181 | $ 10,541
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 13,976 | $ 13,176
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 25,629 | $ 24,915
Common equity tier one risk based capital to risk weighted assets | 0.154 | 0.139
Common equity tier one capital required for capital adequacy | $ 11,655 | $ 12,577
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 10,823 | $ 11,679
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%
Reliance State Bank [Member] | Conducts Business Out of Offices at Story City, Garner, and Kleme, Iowa [Member] |  |
Capital | $ 29,536 | $ 29,222
Capital to risk weighted assets | 0.131 | 0.122
Capital required for capital adequacy | $ 23,619 | $ 25,232
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 22,495 | $ 24,030
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 26,720 | $ 26,237
Tier one risk based capital to risk weighted assets | 0.119 | 0.109
Tier one risk based capital required for capital adequacy | $ 19,120 | $ 20,426
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 17,996 | $ 19,224
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 26,720 | $ 26,237
Tier one leverage capital to average assets | 0.092 | 0.086
Tier one leverage capital required for capital adequacy | $ 11,619 | $ 12,160
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 14,524 | $ 15,200
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 26,720 | $ 26,237
Common equity tier one risk based capital to risk weighted assets | 0.119 | 0.109
Common equity tier one capital required for capital adequacy | $ 15,746 | $ 16,821
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 14,621 | $ 15,620
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%
State Bank and Trust [Member] |  |
Capital | $ 22,860 | $ 22,435
Capital to risk weighted assets | 0.169 | 0.16
Capital required for capital adequacy | $ 14,205 | $ 14,719
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 13,529 | $ 14,018
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 21,182 | $ 20,734
Tier one risk based capital to risk weighted assets | 0.157 | 0.148
Tier one risk based capital required for capital adequacy | $ 11,499 | $ 11,915
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 10,823 | $ 11,214
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 21,182 | $ 20,734
Tier one leverage capital to average assets | 0.109 | 0.102
Tier one leverage capital required for capital adequacy | $ 7,773 | $ 8,096
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 9,717 | $ 10,120
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 21,182 | $ 20,734
Common equity tier one risk based capital to risk weighted assets | 0.157 | 0.148
Common equity tier one capital required for capital adequacy | $ 9,470 | $ 9,812
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 8,794 | $ 9,112
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%
United Bank and Trust [Member] |  |
Capital | $ 13,386 | $ 13,205
Capital to risk weighted assets | 0.172 | 0.164
Capital required for capital adequacy | $ 8,162 | $ 8,479
Capital required for capital adequacy to risk weighted assets | 10.50% | 10.50%
Capital required to be well capitalized | $ 7,773 | $ 8,075
Capital required to be well capitalized to risk weighted assets | 0.10 | 0.10
Tier one risk based capital | $ 12,414 | $ 12,198
Tier one risk based capital to risk weighted assets | 0.16 | 0.151
Tier one risk based capital required for capital adequacy | $ 6,607 | $ 6,864
Tier one risk based capital required for capital adequacy to risk weighted assets | 8.50% | 8.50%
Tier one risk based capital required to be well capitalized | $ 6,219 | $ 6,460
Tier one risk based capital required to be well capitalized to risk weighted assets | 0.08 | 0.08
Tier one leverage capital | $ 12,414 | $ 12,198
Tier one leverage capital to average assets | 0.102 | 0.096
Tier one leverage capital required for capital adequacy | $ 4,891 | $ 5,084
Tier one leverage capital required for capital adequacy to risk weighted assets | 0.04 | 0.04
Tier one leverage capital required to be well capitalized | $ 6,114 | $ 6,356
Tier one leverage capital required to be well capitalized to average assets | 0.05 | 0.05
Common equity tier one capital | $ 12,414 | $ 12,198
Common equity tier one risk based capital to risk weighted assets | 0.16 | 0.151
Common equity tier one capital required for capital adequacy | $ 5,441 | $ 5,653
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | 7.00% | 7.00%
Common equity tier one capital required to be well capitalized | $ 5,053 | $ 5,249
Common equity tier one capital required to be well capitalized to risk weighted assets | 6.50% | 6.50%

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