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v3.25.2

Capital Ratios (Details) $ in Thousands | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Common Equity Tier One Capital | $ 186,605 | $ 183,348
Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Actual | 0.1246 | 0.1221
CommonEquityTierOneRiskRatedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer | $ 104,870 | $ 105,136
CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 7.00% | 7.00%
Tier 1, Actual Amount | $ 186,605 | $ 183,348
Tier 1, Actual Ratio | 0.1246 | 0.1221
Capital Adequacy Minimum with Buffer | $ 127,342 | $ 127,665
TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.0850 | 0.0850
Banking Regulation, Total Capital, Actual | $ 229,759 | $ 226,179
Capital to Risk Weighted Assets | 0.1534 | 0.1506
CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer | $ 157,305 | $ 157,703
CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.1050 | 0.1050
Tier One Leverage Capital | $ 186,605 | $ 183,348
Tier One Leverage Capital Ratio to Average Assets | 0.0904 | 0.0886
TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer | $ 82,580 | $ 82,803
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.0400 | 0.0400
Isabella Bank [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Common Equity Tier One Capital | $ 181,950 | $ 172,589
Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Actual | 0.1218 | 0.1153
CommonEquityTierOneRiskRatedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer | $ 104,553 | $ 104,783
CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 7.00% | 7.00%
Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Well Capitalized, Minimum | $ 97,085 | $ 97,299
Tier 1 Capital to Risk Weighted Asssets | 0.0650 | 0.0650
Tier 1, Actual Amount | $ 181,950 | $ 172,589
Tier 1, Actual Ratio | 0.1218 | 0.1153
Capital Adequacy Minimum with Buffer | $ 126,958 | $ 127,237
TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.0850 | 0.0850
Tier One Risk Based Capital Required to be Well Capitalized | $ 119,490 | $ 119,753
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio | 0.0800 | 0.0800
Banking Regulation, Total Capital, Actual | $ 195,636 | $ 185,997
Capital to Risk Weighted Assets | 0.1310 | 0.1243
CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer | $ 156,830 | $ 157,175
CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.1050 | 0.1050
Capital Required to be Well Capitalized | $ 149,362 | $ 149,691
Capital Required to be Well Capitalized to Risk Weighted Assets | 0.1000 | 0.1000
Tier One Leverage Capital | $ 181,950 | $ 172,589
Tier One Leverage Capital Ratio to Average Assets | 0.0883 | 0.0836
TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer | $ 82,377 | $ 82,602
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer | 0.0400 | 0.0400
Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount | $ 102,972 | $ 103,252
Tier One Leverage Capital Required to be Well Capitalized to Average Assets | 0.0500 | 0.0500

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