Investment Securities (Contractual Maturity Distribution Of Debt Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Amortized Cost	$ 17,918	$ 19,541
Fair Value	15,045	$ 16,869
Debt securities
Available-for-sale, Within one year, Amortized Cost	306
Available-for-sale, After one year through five years, Amortized Cost	1,312
Available-for-sale, After five years through ten years, Amortized Cost	5,119
Available-for-sale, After ten years, Amortized Cost	11,181
Amortized Cost	17,918
Available-for-sale, Within one year, Fair Value	306
Available-for-sale, After one year through five years, Fair Value	1,292
Available-for-sale, After five years through ten years, Fair Value	4,564
Available-for-sale, After ten years, Fair Value	8,883
Fair Value	$ 15,045

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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