Investment Securities (Schedule Of Realized Gain (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Investments, Debt and Equity Securities [Abstract]
Available-for-sale securities, gross realized gains	$ 3	$ 6	$ 21	$ 38
Net realized gain on available-for-sale securities	3	6	21	38
Net realized gain on equity securities	10	40	62	114
Net unrealized (loss) gain on equity securities	(137)	19	(202)	36
Other (loss) gain on investments, net	$ (124)	$ 65	$ (119)	$ 188

Amount of realized gain on 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
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized and unrealized gain (loss) on investment.

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