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Regulatory Capital - Schedule of Actual Capital Amounts and Ratios and Selected Minimum Regulatory Thresholds (Details) $ in Millions | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
--- | --- | ---
Total risk-based capital: |  |
Actual amount | $ 2,875.8 | $ 1,659.3
Capital to Risk Weighted Assets | 0.1248 | 0.1411
Adequately capitalized Basel III phase-in schedule, amount | $ 1,843.2 | $ 940.9
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 0.0800 | 0.0800
Adequately capitalized Basel III fully phased-in, amount | $ 2,419.2 | $ 1,235.0
Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 10.50% | 10.50%
Well capitalized, amount | $ 2,304.0 | $ 1,176.2
Capital Required to be Well Capitalized to Risk Weighted Assets | 0.1000 | 0.1000
Tier 1 risk-based capital: |  |
Actual amount | $ 2,408.8 | $ 1,469.0
Tier One Risk Based Capital to Risk Weighted Assets | 0.1045 | 0.1249
Adequately capitalized Basel III phase-in schedule, amount | $ 1,382.4 | $ 705.7
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 0.0600 | 0.0600
Adequately capitalized Basel III fully phased-in, amount | $ 1,958.4 | $ 999.7
Tier One Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 8.50% | 8.50%
Well capitalized, amount | $ 1,843.2 | $ 940.9
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 0.0800 | 0.0800
Common Equity Tier One Capital [Abstract] |  |
Actual amount | $ 2,408.8 | $ 1,384.8
Common Equity Tier One Risk Based Capital To Risk Weighted Assets | 10.45% | 11.77%
Adequately capitalized Basel III phase-in schedule, amount | $ 1,036.8 | $ 529.3
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 4.50% | 4.50%
Adequately capitalized Basel III fully phased-in, amount | $ 1,612.8 | $ 823.3
Tier One Common Equity Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 7.00% | 7.00%
Well capitalized, amount | $ 1,497.6 | $ 764.5
Common Equity Tier One Capital To Be Well Capitalized To Risk Weighted Assets | 6.50% | 6.50%
Leverage capital ratio: |  |
Actual amount | $ 2,408.8 | $ 1,469.0
Tier One Leverage Capital to Average Assets | 0.0775 | 0.0768
Adequately capitalized, amount | $ 1,242.9 | $ 765.5
Adequately capitalized, ratio (percent) | 0.0400 | 0.0400
Well capitalized, amount | $ 1,553.6 | $ 956.9
Well capitalized, ratio (percent) | 0.0500 | 0.0500
FIB |  |
Total risk-based capital: |  |
Actual amount | $ 2,713.5 | $ 1,472.5
Capital to Risk Weighted Assets | 0.1180 | 0.1256
Adequately capitalized Basel III phase-in schedule, amount | $ 1,839.6 | $ 938.0
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 0.0800 | 0.0800
Adequately capitalized Basel III fully phased-in, amount | $ 2,414.5 | $ 1,231.1
Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 10.50% | 10.50%
Well capitalized, amount | $ 2,299.5 | $ 1,172.5
Capital Required to be Well Capitalized to Risk Weighted Assets | 0.1000 | 0.1000
Tier 1 risk-based capital: |  |
Actual amount | $ 2,504.1 | $ 1,382.2
Tier One Risk Based Capital to Risk Weighted Assets | 0.1089 | 0.1179
Adequately capitalized Basel III phase-in schedule, amount | $ 1,379.7 | $ 703.5
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 0.0600 | 0.0600
Adequately capitalized Basel III fully phased-in, amount | $ 1,954.6 | $ 996.6
Tier One Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 8.50% | 8.50%
Well capitalized, amount | $ 1,839.6 | $ 938.0
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 0.0800 | 0.0800
Common Equity Tier One Capital [Abstract] |  |
Actual amount | $ 2,504.1 | $ 1,382.2
Common Equity Tier One Risk Based Capital To Risk Weighted Assets | 10.89% | 11.79%
Adequately capitalized Basel III phase-in schedule, amount | $ 1,034.8 | $ 527.6
Adequately capitalized Basel III phase-in schedule, ratio (percent) | 4.50% | 4.50%
Adequately capitalized Basel III fully phased-in, amount | $ 1,609.7 | $ 820.8
Tier One Common Equity Capital Required For Capital Adequacy Under Basel III Fully Phased-In To Risk Weighted Assets | 7.00% | 7.00%
Well capitalized, amount | $ 1,494.7 | $ 762.1
Common Equity Tier One Capital To Be Well Capitalized To Risk Weighted Assets | 6.50% | 6.50%
Leverage capital ratio: |  |
Actual amount | $ 2,504.1 | $ 1,382.2
Tier One Leverage Capital to Average Assets | 0.0807 | 0.0724
Adequately capitalized, amount | $ 1,241.1 | $ 764.1
Adequately capitalized, ratio (percent) | 0.0400 | 0.0400
Well capitalized, amount | $ 1,551.4 | $ 955.1
Well capitalized, ratio (percent) | 0.0500 | 0.0500

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