Regulatory Requirements - Narratives (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Dec. 31, 2021
Regulated Operations [Abstract]
Common equity tier one risk-based capital ratio, internal minimum	11.00%
Tier one risk-based capital ratio, internal minimum	11.00%
Total risk-based capital ratio, internal minimum	13.00%
Tier one leverage ratio, internal minimum	11.00%
Capital benefit used in the computation of common equity tier one capital		$ 35

Banking Regulation, Capital Benefit Used In The Computation Of Common Equity Tier One Capital

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Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Internal Minimum

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Banking Regulation, Tier One Leverage Capital Ratio, Internal Minimum

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Banking Regulation, Tier One Risk-Based Capital Ratio, Internal Minimum

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Banking Regulation, Total Risk-Based Capital Ratio, Internal Minimum

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