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	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 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	$ (170)	$ 15	$ (221)	$ 136
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	$ 170	$ (25)	$ 221	$ (145)
Cumulative amount of fair value hedging adjustments to hedged fixed rate debt	$ (322)		$ (322)

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

9 Months Ended

Sep. 30, 2026

Sep. 30, 2025

Sep. 30, 2026

Sep. 30, 2025

Interest rate contracts

Derivative Instruments, Gain (Loss) [Line Items]

Location

Interest, net

Gain/(loss) recognized in income on derivatives

$ (170)

$ 15

$ (221)

$ 136

Hedged fixed rate debt

Derivative Instruments, Gain (Loss) [Line Items]

Location

Interest, net

Gain/(loss) recognized in income on derivatives

$ 170

$ (25)

$ 221

$ (145)

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

$ (322)

- 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