Investment Securities (Schedule of Unrealized Loss on Investments) (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	$ 25,322	$ 21,288
Debt securities, available-for-sale, unrealized loss, less than 12 months	(2,700)	(373)
Debt securities, available-for-sale, fair value, 12 months or longer	5,861	896
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(1,083)	(48)
U.S. Treasury and federal agencies
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	1,965	1,682
Debt securities, available-for-sale, unrealized loss, less than 12 months	(137)	(20)
Debt securities, available-for-sale, fair value, 12 months or longer	409	0
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(50)	0
U.S. States and political subdivisions
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	604	160
Debt securities, available-for-sale, unrealized loss, less than 12 months	(68)	(3)
Debt securities, available-for-sale, fair value, 12 months or longer	41	31
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(4)	(1)
Foreign government
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	121	76
Debt securities, available-for-sale, unrealized loss, less than 12 months	(8)	(2)
Debt securities, available-for-sale, fair value, 12 months or longer	25	7
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(4)	0
Agency mortgage-backed securities
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	13,719	12,244
Debt securities, available-for-sale, unrealized loss, less than 12 months	(1,361)	(223)
Debt securities, available-for-sale, fair value, 12 months or longer	4,044	38
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(737)	(1)
Mortgage-backed residential
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	4,319	3,243
Debt securities, available-for-sale, unrealized loss, less than 12 months	(552)	(34)
Debt securities, available-for-sale, fair value, 12 months or longer	267	22
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(43)	0
Agency mortgage-backed commercial
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	2,753	2,553
Debt securities, available-for-sale, unrealized loss, less than 12 months	(419)	(70)
Debt securities, available-for-sale, fair value, 12 months or longer	812	749
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(197)	(43)
Asset-backed
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	425	360
Debt securities, available-for-sale, unrealized loss, less than 12 months	(21)	(3)
Debt securities, available-for-sale, fair value, 12 months or longer	14	0
Debt securities, available-for-sale, unrealized loss, 12 months or longer	0	0
Corporate debt
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	1,416	970
Debt securities, available-for-sale, unrealized loss, less than 12 months	(134)	(18)
Debt securities, available-for-sale, fair value, 12 months or longer	249	49
Debt securities, available-for-sale, unrealized loss, 12 months or longer	$ (48)	$ (3)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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