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Note 7 - Regulatory Capital - Actual and Required Capital Amount and Ratio (Details) $ in Thousands | Sep. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
--- | --- | ---
Consolidated Waterstone Financial Inc [Member] |  |
Total capital (to risk-weighted assets) | $ 376,646 | $ 376,624
Total capital (to risk-weighted assets) Ratio | 0.2046 | 0.209
Total capital (to risk-weighted assets), For Capital Adequacy Ratio | 0.08 | 0.08
Total capital (to risk-weighted assets), Minimum Capital Adequacy with Capital Buffer Ratio | 10.50% | 10.50%
Tier I capital (to risk-weighted assets) | $ 357,971 | $ 357,135
Tier I capital (to risk-weighted assets) Ratio | 0.1945 | 0.1981
Tier I capital (to risk-weighted assets), For Capital Adequacy Ratio | 0.06 | 0.06
Tier I capital (to risk weighted assets), Minimum Capital Adequacy with Capital Buffer Ratio | 8.50% | 8.50%
Common Equity Tier 1 Capital (to risk-weighted assets) | $ 357,971 | $ 357,135
Common Equity Tier 1 capital (to risk-weighted assets) Ratio | 0.1945 | 0.1981
Common Equity Tier I capital (to risk-weighted), For Capital Adequacy Ratio | 0.045 | 0.045
Common Equity Tier I capital (to risk weighted), Minimum Capital Adequacy with Capital Buffer Ratio | 7.00% | 7.00%
Tier I capital (to average assets) | $ 357,971 | $ 357,135
Tier I capital (to average assets) Ratio | 0.1945 | 0.1604
Tier I capital (to average assets), For Capital Adequacy Ratio | 0.04 | 0.04
Total capital (to risk-weighted assets), For Capital Adequacy Purposes |  | $ 144,162
Total capital (to risk-weighted assets), Minimum Capital Adequacy with Capital Buffer |  | 189,213
Tier I capital (to risk-weighted assets), For Capital Adequacy Purposes |  | 108,168
Tier I capital (to risk weighted assets), Minimum Capital Adequacy with Capital Buffer |  | 153,238
Common Equity Tier I capital (to risk weighted assets), For Capital Adequacy Purposes |  | 81,126
Common Equity Tier I capital (to risk weighted assets) Minimum Capital Adequacy with Capital Buffer |  | 126,196
Tier I capital (to average assets), For Capital Adequacy Purposes |  | 89,061
Subsidiaries [Member] |  |
Total capital (to risk-weighted assets) | $ 364,300 | $ 365,634
Total capital (to risk-weighted assets) Ratio | 0.1979 | 0.2029
Total capital (to risk-weighted assets), For Capital Adequacy Ratio | 0.08 | 0.08
Total capital (to risk-weighted assets), Minimum Capital Adequacy with Capital Buffer Ratio | 10.50% | 10.50%
Total capital (to risk-weighted assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions Ratio | 0.10 | 0.10
Tier I capital (to risk-weighted assets) | $ 345,625 | $ 346,145
Tier I capital (to risk-weighted assets) Ratio | 0.1878 | 0.1921
Tier I capital (to risk-weighted assets), For Capital Adequacy Ratio | 0.06 | 0.06
Tier I capital (to risk weighted assets), Minimum Capital Adequacy with Capital Buffer Ratio | 8.50% | 8.50%
Tier I capital (to risk-weighted assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions Ratio | 0.08 | 0.08
Common Equity Tier 1 Capital (to risk-weighted assets) | $ 345,625 | $ 346,145
Common Equity Tier 1 capital (to risk-weighted assets) Ratio | 0.1878 | 0.1921
Common Equity Tier I capital (to risk-weighted), For Capital Adequacy Ratio | 0.045 | 0.045
Common Equity Tier I capital (to risk weighted), Minimum Capital Adequacy with Capital Buffer Ratio | 7.00% | 7.00%
Common Equity Tier I capital (to risk-weighted) , To Be Well-Capitalized Under Prompt Corrective Action Provisions Ratio | 0.065 | 0.065
Tier I capital (to average assets) | $ 345,625 | $ 346,145
Tier I capital (to average assets) Ratio | 0.1878 | 0.1555
Tier I capital (to average assets), For Capital Adequacy Ratio | 0.04 | 0.04
Tier I capital (to average assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions Ratio | 0.05 | 0.05
State of Wisconsin (to total assets) | $ 345,625 | $ 346,145
State of Wisconsin (to total assets) Ratio | 15.24% | 15.68%
State of Wisconsin (to total assets), For Capital Adequacy Ratio | 6.00% | 6.00%
Total capital (to risk-weighted assets), For Capital Adequacy Purposes |  | $ 144,167
Total capital (to risk-weighted assets), Minimum Capital Adequacy with Capital Buffer |  | 189,220
Total capital (to risk-weighted assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions |  | 180,209
Tier I capital (to risk-weighted assets), For Capital Adequacy Purposes |  | 108,126
Tier I capital (to risk weighted assets), Minimum Capital Adequacy with Capital Buffer |  | 153,178
Tier I capital (to risk-weighted assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions |  | 144,168
Common Equity Tier I capital (to risk weighted assets), For Capital Adequacy Purposes |  | 81,094
Common Equity Tier I capital (to risk weighted assets) Minimum Capital Adequacy with Capital Buffer |  | 126,147
Common Equity Tier I capital (to risk-weighted assets), To Be Well-Capitalized Under Prompt Corrective Action Provisions |  | 117,136
Tier I capital (to average assets), For Capital Adequacy Purposes |  | 89,041
Amount of minimum Tier 1 leverage capital categorized as well capitalized as defined by regulatory framework for prompt corrective action. |  | 111,301
State of Wisconsin (to total assets), For Capital Adequacy Purposes |  | $ 132,453

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