Investment Securities (Contractual Maturity Distribution Of Debt Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Investment securities available-for-sale, Amortized Cost	$ 19,541	$ 22,045
Investment Securities, Available-for-sale	16,869	$ 19,012
Debt securities
Available-for-sale, Within one year, Amortized Cost	813
Available-for-sale, After one year through five years, Amortized Cost	1,098
Available-for-sale, After five years through ten years, Amortized Cost	5,380
Available-for-sale, After ten years, Amortized Cost	12,250
Investment securities available-for-sale, Amortized Cost	19,541
Available-for-sale, Within one year, Fair Value	790
Available-for-sale, After one year through five years, Fair Value	1,034
Available-for-sale, After five years through ten years, Fair Value	4,869
Available-for-sale, After ten years, Fair Value	10,176
Investment Securities, Available-for-sale	$ 16,869

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
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-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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