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Note 15 - Regulatory Capital - Schedule of Comparison (Details) $ in Thousands | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
--- | --- | ---
Parent Company [Member] |  |
Actual, Capital, Rate | 0.1453 | 0.1373
Actual, Tier 1 Risk-based Rate | 0.1136 | 0.1051
Actual, Tier 1 Leverage Rate | 0.0987 | 0.0901
Actual, CET 1 Rate | 0.1136 | 0.1051
Total risk-based capital (to risk-weighted assets) | 0.1453 | 0.1373
Tier 1 risk-based capital (to risk-weighted assets) | 0.1136 | 0.1051
Tier 1 leverage capital (to average assets) | 0.0987 | 0.0901
CET 1 capital (to risk-weighted assets) | 0.1136 | 0.1051
The 1st Security Bank of Washington, Subsidiary [Member] |  |
Actual, Capital | $ 368,953 | $ 339,436
Actual, Capital, Rate | 0.1418 | 0.1337
Capital Adequacy, Total | $ 208,174 | $ 203,094
Capital Adequacy, Total Rate | 0.08 | 0.08
Capital Adequacy, Total Risk-based with Buffer | $ 273,228 | $ 266,561
Capital Adequacy, Total Risk-based with Buffer, Rate | 0.105 | 0.105
Well Capitalized, Total Capital | $ 260,218 | $ 253,868
Well Capitalized, Total Capital Rate | 0.10 | 0.10
Actual, Tier 1 Risk-based | $ 336,416 | $ 307,686
Actual, Tier 1 Risk-based Rate | 0.1293 | 0.1212
Capital Adequacy, Tier 1 Risk-based | $ 156,131 | $ 152,321
Capital Adequacy, Tier 1 Risk-based Rate | 0.06 | 0.06
Capital Adequacy, Tier 1 Risk-based with Buffer | $ 221,185 | $ 215,787
Capital Adequacy, Tier 1 Risk-based with Buffer, Rate | 0.085 | 0.085
Well Capitalized, Tier 1 Risk-based | $ 208,174 | $ 203,094
Well Capitalized, Tier 1 Risk-based Rate | 0.08 | 0.08
Actual, Tier 1 Leverage | $ 336,416 | $ 307,686
Actual, Tier 1 Leverage Rate | 0.1124 | 0.1039
Capital Adequacy, Tier 1 Leverage | $ 119,741 | $ 118,488
Capital Adequacy, Tier 1 Leverage Rate | 0.04 | 0.04
Well Capitalized, Tier 1 Leverage | $ 149,676 | $ 148,109
Well Capitalized, Tier 1 Leverage Rate | 0.05 | 0.05
Actual, CET 1 | $ 336,416 | $ 307,686
Actual, CET 1 Rate | 0.1293 | 0.1212
Capital Adequacy, CET 1 | $ 117,098 | $ 114,240
Capital Adequacy, CET 1 Rate | 0.045 | 0.045
Capital Adequacy, CET 1 with Buffer | $ 182,152 | $ 177,707
Capital Adequacy, CET 1 with Buffer , Rate | 0.07 | 0.07
Well Capitalized, CET 1 | $ 169,141 | $ 165,014
Well Capitalized, CET 1 Rate | 0.065 | 0.065
Total risk-based capital (to risk-weighted assets) | 0.1418 | 0.1337
Tier 1 risk-based capital (to risk-weighted assets) | 0.1293 | 0.1212
Tier 1 leverage capital (to average assets) | 0.1124 | 0.1039
CET 1 capital (to risk-weighted assets) | 0.1293 | 0.1212

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