Investment Securities (Schedule of Unrealized Loss on Investments) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	$ 19,595	$ 21,288
Debt securities, available-for-sale, unrealized loss, less than 12 months	(3,013)	(373)
Debt securities, available-for-sale, fair value, 12 months or longer	9,935	896
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(2,588)	(48)
Hedged asset, fair value hedge, cumulative increase (decrease)	25
U.S. Treasury and federal agencies
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	1,192	1,682
Debt securities, available-for-sale, unrealized loss, less than 12 months	(140)	(20)
Debt securities, available-for-sale, fair value, 12 months or longer	807	0
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(137)	0
U.S. States and political subdivisions
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	615	160
Debt securities, available-for-sale, unrealized loss, less than 12 months	(82)	(3)
Debt securities, available-for-sale, fair value, 12 months or longer	104	31
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(24)	(1)
Foreign government
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	86	76
Debt securities, available-for-sale, unrealized loss, less than 12 months	(5)	(2)
Debt securities, available-for-sale, fair value, 12 months or longer	50	7
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(7)	0
Agency mortgage-backed residential
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	11,109	12,244
Debt securities, available-for-sale, unrealized loss, less than 12 months	(1,743)	(223)
Debt securities, available-for-sale, fair value, 12 months or longer	5,566	38
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(1,467)	(1)
Mortgage-backed residential
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	3,688	3,243
Debt securities, available-for-sale, unrealized loss, less than 12 months	(681)	(34)
Debt securities, available-for-sale, fair value, 12 months or longer	674	22
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(166)	0
Agency mortgage-backed commercial
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	1,361	2,553
Debt securities, available-for-sale, unrealized loss, less than 12 months	(217)	(70)
Debt securities, available-for-sale, fair value, 12 months or longer	2,143	749
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(666)	(43)
Asset-backed
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	391	360
Debt securities, available-for-sale, unrealized loss, less than 12 months	(17)	(3)
Debt securities, available-for-sale, fair value, 12 months or longer	73	0
Debt securities, available-for-sale, unrealized loss, 12 months or longer	(6)	0
Corporate debt
Debt Securities [Line Items]
Debt securities, available-for-sale, fair value, less than 12 months	1,153	970
Debt securities, available-for-sale, unrealized loss, less than 12 months	(128)	(18)
Debt securities, available-for-sale, fair value, 12 months or longer	518	49
Debt securities, available-for-sale, unrealized loss, 12 months or longer	$ (115)	$ (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.

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