Investment Securities (Contractual Maturity Distribution Of Debt Securities) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Investment securities available-for-sale, Amortized Cost	$ 22,785	$ 17,116
Investment securities available-for-sale, Fair Value	20,829	$ 16,986
Debt securities
Available-for-sale, Within one year, Amortized Cost	1,101
Available-for-sale, After one year through five years, Amortized Cost	2,092
Available-for-sale, After five years through ten years, Amortized Cost	5,018
Available-for-sale, After ten years, Amortized Cost	14,574
Investment securities available-for-sale, Amortized Cost	22,785
Available-for-sale, Within one year, Fair Value	1,096
Available-for-sale, After one year through five years, Fair Value	1,971
Available-for-sale, After five years through ten years, Fair Value	4,787
Available-for-sale, After ten years, Fair Value	12,975
Investment securities available-for-sale, Fair Value	$ 20,829

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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