Risk Management - Effect of Derivative Contracts on the Income Statement (Details) - Derivatives designated as hedging instruments - Derivatives in fair value hedging relationships - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Interest rate contracts
Derivative Instruments, Gain (Loss) [Line Items]
Location	Interest, net	Interest, net	Interest, net	Interest, net
Gain/(loss) recognized in income on derivatives	$ (34)	$ 41	$ (51)	$ 121
Hedged fixed rate debt
Derivative Instruments, Gain (Loss) [Line Items]
Location	Interest, net	Interest, net	Interest, net	Interest, net
Gain/(loss) recognized in income on derivatives	$ 35	$ (41)	$ 51	$ (120)
Cumulative amount of fair value hedging adjustments to hedged fixed rate debt	$ (152)		$ (152)

Risk Management - Effect of Derivative Contracts on the Income Statement (Details) - Derivatives designated as hedging instruments - Derivatives in fair value hedging relationships - USD ($)
$ in Millions

3 Months Ended

6 Months Ended

Jun. 30, 2026

Jun. 30, 2025

Jun. 30, 2026

Jun. 30, 2025

Interest rate contracts

Derivative Instruments, Gain (Loss) [Line Items]

Location

Interest, net

Gain/(loss) recognized in income on derivatives

$ (34)

$ 41

$ (51)

$ 121

Hedged fixed rate debt

Derivative Instruments, Gain (Loss) [Line Items]

Location

Interest, net

Gain/(loss) recognized in income on derivatives

$ 35

$ (41)

$ 51

$ (120)

Cumulative amount of fair value hedging adjustments to hedged fixed rate debt

$ (152)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details