Debt - Schedule of Short-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Short-term Debt [Line Items]
Federal Home Loan Bank	$ 5,175	$ 4,150
Securities sold under agreements to repurchase	741	545
Total short-term borrowings	5,916	4,695
Cash collateral placed	5	1
U.S. Treasury and federal agencies
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	511
Agency mortgage-backed residential
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	230
Maturity Within 30 Days
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	517
Maturity 31 to 60 Days
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	109
Maturity 61 to 90 Days
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	115
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	5,175	4,150
Securities sold under agreements to repurchase	741	545
Total short-term borrowings	$ 5,916	$ 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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