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Note 12 - Regulatory Capital - Schedule of Comparison (Details) $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Parent Company [Member] |  |
Actual, Capital, Rate | 0.1393 | 0.1453
Actual, Tier 1 Risk-based Rate | 0.1095 | 0.1136
Actual, Tier 1 Leverage Rate | 0.0949 | 0.0987
Actual, CET 1 Rate | 0.1095 | 0.1136
Total risk-based capital (to risk-weighted assets) | 0.1393 | 0.1453
Tier 1 risk-based capital (to risk-weighted assets) | 0.1095 | 0.1136
Tier 1 leverage capital (to average assets) | 0.0949 | 0.0987
CET 1 capital (to risk-weighted assets) | 0.1095 | 0.1136
The 1st Security Bank of Washington, Subsidiary [Member] |  |
Actual, Capital | $ 382,049 | $ 368,953
Actual, Capital, Rate | 0.1381 | 0.1418
Capital Adequacy, Total | $ 221,372 | $ 208,174
Capital Adequacy, Total Rate | 0.08 | 0.08
Capital Adequacy, Total Risk-based with Buffer | $ 290,551 | $ 273,228
Capital Adequacy, Total Risk-based with Buffer, Rate | 0.105 | 0.105
Well Capitalized, Total Capital | $ 276,715 | $ 260,218
Well Capitalized, Total Capital Rate | 0.10 | 0.10
Actual, Tier 1 Risk-based | $ 349,690 | $ 336,416
Actual, Tier 1 Risk-based Rate | 0.1264 | 0.1293
Capital Adequacy, Tier 1 Risk-based | $ 166,029 | $ 156,131
Capital Adequacy, Tier 1 Risk-based Rate | 0.06 | 0.06
Capital Adequacy, Tier 1 Risk-based with Buffer | $ 235,208 | $ 221,185
Capital Adequacy, Tier 1 Risk-based with Buffer, Rate | 0.085 | 0.085
Well Capitalized, Tier 1 Risk-based | $ 221,372 | $ 208,174
Well Capitalized, Tier 1 Risk-based Rate | 0.08 | 0.08
Actual, Tier 1 Leverage | $ 349,690 | $ 336,416
Actual, Tier 1 Leverage Rate | 0.1096 | 0.1124
Capital Adequacy, Tier 1 Leverage | $ 127,647 | $ 119,741
Capital Adequacy, Tier 1 Leverage Rate | 0.04 | 0.04
Well Capitalized, Tier 1 Leverage | $ 159,558 | $ 149,676
Well Capitalized, Tier 1 Leverage Rate | 0.05 | 0.05
Actual, CET 1 | $ 349,690 | $ 336,416
Actual, CET 1 Rate | 0.1264 | 0.1293
Capital Adequacy, CET 1 | $ 124,522 | $ 117,098
Capital Adequacy, CET 1 Rate | 0.045 | 0.045
Capital Adequacy, CET 1 with Buffer | $ 193,701 | $ 182,152
Capital Adequacy, CET 1 with Buffer , Rate | 0.07 | 0.07
Well Capitalized, CET 1 | $ 179,865 | $ 169,141
Well Capitalized, CET 1 Rate | 0.065 | 0.065
Total risk-based capital (to risk-weighted assets) | 0.1381 | 0.1418
Tier 1 risk-based capital (to risk-weighted assets) | 0.1264 | 0.1293
Tier 1 leverage capital (to average assets) | 0.1096 | 0.1124
CET 1 capital (to risk-weighted assets) | 0.1264 | 0.1293

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