Long-Term Debt - FHLB Advances (Details) - Subsidiaries - FHLB Advances Due 2021 to 2047 $ in Millions	Dec. 31, 2024 USD ($)
Debt Instrument
Loans and securities serving as FHLB collateral	$ 36,600
FHLB advances	1,500
FHLB maturing in 2025	3
FHLB maturing in 2026	1,500
FHLB maturing after 2029	$ 5
Weighted-Average
Debt Instrument
Interest rate (as a percent)	4.91%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of advance from Federal Home Loan Bank (FHLBank) maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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