Debt - Schedule of Short-term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Short-term Debt [Line Items]
Federal Home Loan Bank	$ 3,600	$ 4,150
Securities sold under agreements to repurchase	526	545
Total short-term borrowings	4,126	4,695
Cash collateral placed	10	1
U.S. Treasury and federal agencies
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	526
Maturity Within 30 Days
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	427
Maturity 31 to 60 Days
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	99
Unsecured
Short-term Debt [Line Items]
Federal Home Loan Bank	0	0
Securities sold under agreements to repurchase	0	0
Total short-term borrowings	0	0
Secured debt
Short-term Debt [Line Items]
Federal Home Loan Bank	3,600	4,150
Securities sold under agreements to repurchase	526	545
Total short-term borrowings	$ 4,126	$ 4,695

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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