Investment Securities (Schedule Of Realized Gain (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Available-for-sale securities, gross realized gains	$ 18	$ 32
Net realized gains on available-for-sale securities	18	32
Net realized gain on equity securities	52	74
Net unrealized (loss) gain on equity securities	(65)	17
Other gain on investments, net	$ 5	$ 123

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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-Section 50
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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).

+ References

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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).

+ References

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

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