Supplemental Financial Statement Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Other Income and Expenses [Abstract]
Interest income	$ 2	$ 4

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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+ Details