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Note 16 - Regulatory Matters - Actual Capital Amounts and Ratios (Details) $ in Thousands | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
--- | --- | ---
Tier one leverage capital |  |  | $ 167,544
Tier one leverage capital to average assets |  |  | 0.101
Capital |  |  | $ 180,834
Capital to risk weighted assets |  |  | 0.143
Capital required for capital adequacy | [1] |  | $ 132,878
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Tier one risk based capital |  |  | $ 167,514
Tier one risk based capital to risk weighted assets |  |  | 0.132
Tier one risk based capital required for capital adequacy | [1] |  | $ 107,568
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one leverage capital required for capital adequacy | [1] |  | $ 66,234
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 167,544
Common equity tier one risk based capital to risk weighted assets |  |  | 0.132
Common equity tier one capital required for capital adequacy | [1] |  | $ 88,585
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Boone Bank and Trust [Member] |  |  |
Tier one leverage capital |  | $ 13,967 | $ 13,274
Tier one leverage capital to average assets |  | 0.092 | 0.095
Tier one leverage capital required to be well capitalized |  | $ 12,170 | $ 7,005
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 14,205
Capital to risk weighted assets |  |  | 0.141
Capital required for capital adequacy | [1] |  | $ 10,610
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 10,105
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 13,274
Tier one risk based capital to risk weighted assets |  |  | 0.131
Tier one risk based capital required for capital adequacy | [1] |  | $ 8,589
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 8,084
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 5,604
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 13,274
Common equity tier one risk based capital to risk weighted assets |  |  | 0.131
Common equity tier one capital required for capital adequacy | [1] |  | $ 7,074
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 6,568
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
First National Bank [Member] | Also Conducts Business Out of 3 Full Service Offices in Des Moines Metro Area [Member] |  |  |
Tier one leverage capital |  | $ 86,071 | $ 80,665
Tier one leverage capital to average assets |  | 0.086 | 0.093
Tier one leverage capital required to be well capitalized |  | $ 80,393 | $ 43,378
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 87,375
Capital to risk weighted assets |  |  | 0.139
Capital required for capital adequacy | [1] |  | $ 66,180
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 63,028
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 80,665
Tier one risk based capital to risk weighted assets |  |  | 0.128
Tier one risk based capital required for capital adequacy | [1] |  | $ 53,574
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 50,423
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 34,702
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 80,665
Common equity tier one risk based capital to risk weighted assets |  |  | 0.128
Common equity tier one capital required for capital adequacy | [1] |  | $ 44,120
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 40,968
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
Iowa State Savings Bank [Member] |  |  |
Tier one leverage capital |  | $ 21,610 | $ 20,151
Tier one leverage capital to average assets |  | 0.094 | 0.095
Tier one leverage capital required to be well capitalized |  | $ 18,321 | $ 10,776
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 20,495
Capital to risk weighted assets |  |  | 0.142
Capital required for capital adequacy | [1] |  | $ 15,200
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 14,476
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 20,151
Tier one risk based capital to risk weighted assets |  |  | 0.139
Tier one risk based capital required for capital adequacy | [1] |  | $ 12,305
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 11,581
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 8,621
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 20,151
Common equity tier one risk based capital to risk weighted assets |  |  | 0.139
Common equity tier one capital required for capital adequacy | [1] |  | $ 10,133
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 9,410
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
Reliance State Bank [Member] | Conducts Business Out of Offices at Story City, Garner, and Kleme, Iowa [Member] |  |  |
Tier one leverage capital |  | $ 23,278 | $ 22,166
Tier one leverage capital to average assets |  | 0.094 | 0.100
Tier one leverage capital required to be well capitalized |  | $ 19,741 | $ 11,108
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 24,487
Capital to risk weighted assets |  |  | 0.130
Capital required for capital adequacy | [1] |  | $ 19,778
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 18,836
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 22,166
Tier one risk based capital to risk weighted assets |  |  | 0.118
Tier one risk based capital required for capital adequacy | [1] |  | $ 16,010
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 15,069
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 8,886
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 22,166
Common equity tier one risk based capital to risk weighted assets |  |  | 0.118
Common equity tier one capital required for capital adequacy | [1] |  | $ 13,185
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 12,243
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
State Bank and Trust [Member] |  |  |
Tier one leverage capital |  | $ 16,564 | $ 15,233
Tier one leverage capital to average assets |  | 0.085 | 0.095
Tier one leverage capital required to be well capitalized |  | $ 15,657 | $ 7,980
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 16,800
Capital to risk weighted assets |  |  | 0.135
Capital required for capital adequacy | [1] |  | $ 13,115
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 12,490
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 15,233
Tier one risk based capital to risk weighted assets |  |  | 0.122
Tier one risk based capital required for capital adequacy | [1] |  | $ 10,617
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 9,992
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 6,384
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 15,233
Common equity tier one risk based capital to risk weighted assets |  |  | 0.122
Common equity tier one capital required for capital adequacy | [1] |  | $ 8,743
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 8,119
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
United Bank and Trust [Member] |  |  |
Tier one leverage capital |  | $ 10,539 | $ 9,955
Tier one leverage capital to average assets |  | 0.092 | 0.098
Tier one leverage capital required to be well capitalized |  | $ 9,180 | $ 5,091
Tier one leverage capital required to be well capitalized to average assets |  | 0.080 | 0.050
Capital |  |  | $ 10,775
Capital to risk weighted assets |  |  | 0.143
Capital required for capital adequacy | [1] |  | $ 7,910
Capital required for capital adequacy to risk weighted assets | [1] |  | 10.50%
Capital required to be well capitalized |  |  | $ 7,534
Capital required to be well capitalized to risk weighted assets |  |  | 0.100
Tier one risk based capital |  |  | $ 9,955
Tier one risk based capital to risk weighted assets |  |  | 0.132
Tier one risk based capital required for capital adequacy | [1] |  | $ 6,403
Tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 8.50%
Tier one risk based capital required to be well capitalized |  |  | $ 6,027
Tier one risk based capital required to be well capitalized to risk weighted assets |  |  | 0.080
Tier one leverage capital required for capital adequacy | [1] |  | $ 4,073
Tier one leverage capital required for capital adequacy to risk weighted assets | [1] |  | 0.0400
Common equity tier one capital |  |  | $ 9,955
Common equity tier one risk based capital to risk weighted assets |  |  | 0.132
Common equity tier one capital required for capital adequacy | [1] |  | $ 5,273
Common equity tier one risk based capital required for capital adequacy to risk weighted assets | [1] |  | 7.00%
Common equity tier one capital required to be well capitalized |  |  | $ 4,897
Common equity tier one capital required to be well capitalized to risk weighted assets |  |  | 6.50%
[1] | These ratios for December 31, 2019 include a capital conservation buffer of 2.50%, except for the Tier 1 capital to average assets ratios.

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