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Regulatory Capital and Reserve Requirements Regulatory Capital and Reserve Requirements (Narrative) (Details) $ in Millions | 12 Months Ended
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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 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 + Details
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