Comprehensive Income (Loss) (Components Of Accumulated Other Comprehensive Income (Loss), Net Of Tax, In The Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Comprehensive Income (Loss) [Line Items]
Beginning balance			$ 7,038
Net increase (decrease) during the period	$ (271)	$ (61)	(1,078)	$ (99)
Ending balance	5,334	6,758	5,334	6,758
URA(D) On Securities [Member]
Comprehensive Income (Loss) [Line Items]
Beginning balance	(675)	255	122	313
Net increase (decrease) during the period	(242)	(41)	(1,039)	(100)
Ending balance	(917)	213	(917)	213
Foreign Currency Translation Adjustments [Member]
Comprehensive Income (Loss) [Line Items]
Beginning balance	8	45	20	29
Net increase (decrease) during the period	(29)	(21)	(41)	(5)
Ending balance	(21)	24	(21)	24
Benefit Plan Net Gain (Loss) [Member]
Comprehensive Income (Loss) [Line Items]
Beginning balance	(50)	(70)	(50)	(74)
Net increase (decrease) during the period		2	2	6
Ending balance	(49)	(68)	(49)	(68)
Accumulated Other Comprehensive Income (Loss) [Member]
Comprehensive Income (Loss) [Line Items]
Beginning balance	(716)	230	91	268
Net increase (decrease) during the period	(271)	(61)	(1,078)	(99)
Ending balance	$ (987)	$ 169	$ (987)	$ 169