Regulatory Capital and Reserve Requirements Regulatory Capital and Reserve Requirements (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Dividends available to be paid to parent company without obtaining prior approval from bank regulatory agencies	$ 782
Dividends from bank subsidiaries	$ 200	$ 675	$ 1,000
Banking Regulation, Total Risk-Based Capital Ratio, Well Capitalized, Minimum	0.10	0.06
U.S. Banking Subsidiaries
Total capital to risk-weighted assets	0.10
Tier 1 risk-based capital minimum to be well capitalized	0.08
Common equity tier 1 risk-based capital minimum to be well capitalized	6.50%
Banking Regulation, Tier 1 Leverage Capital Ratio, Well Capitalized, Minimum	0.05

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- Definition

Common Equity Tier One Capital Required To Be Well Capitalized To Risk Weighted Assets

+ References

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- Definition

Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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- Definition

Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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- Definition

Amount of dividends that can be declared or paid with approval of regulatory agency.

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- Definition

Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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