Fair Values - Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Investment securities:
Equity securities	$ 44	$ 46
Debt securities	2,581
Derivative, gross, assets	488	174
Liabilities
Derivatives, gross, liabilities	161	1,120
Fair Value, Recurring
Investment securities:
Equity securities	44	46
Debt securities	2,581	997
Derivative, gross, assets	488	174
Total Assets	3,113	1,216
Liabilities
Derivatives, gross, liabilities	161	1,120
Total Liabilities	161	1,120
Level 1 \| Fair Value, Recurring
Investment securities:
Equity securities	44	46
Debt securities	496	0
Derivative, gross, assets	0	0
Total Assets	540	46
Liabilities
Derivatives, gross, liabilities	0	0
Total Liabilities	0	0
Level 2 \| Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	2,004	916
Derivative, gross, assets	487	164
Total Assets	2,491	1,080
Liabilities
Derivatives, gross, liabilities	161	1,120
Total Liabilities	161	1,120
Level 3 \| Fair Value, Recurring
Investment securities:
Equity securities	0	0
Debt securities	81	81
Derivative, gross, assets	1	10
Total Assets	82	91
Liabilities
Derivatives, gross, liabilities	0	0
Total Liabilities	$ 0	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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