Investment Securities - Gains and Losses Recognized in Income from Securities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Available-for-sale debt and other securities:
Realized gains	$ 5	$ 34	$ 16
Realized losses	(2)	(30)	(13)
Impairment losses	(21)	(5)	(1)
Net (losses) gains on available-for-sale debt and other securities	(18)	(1)	2
Trading debt securities:
Net realized losses	0	0	(2)
Net unrealized gains	0	3	11
Net trading debt securities gains	0	3	9
Equity securities:
Net realized gains	15	5	1
Net unrealized gains (losses)	18	11	(96)
Net equity securities gains (losses)	33	16	(95)
Total (losses) gains recognized in income from available-for-sale debt and other securities, trading debt securities and equity securities	15	18	(84)
Commercial Banking Revenue and Wealth and Asset Management Revenue
Equity securities:
Total (losses) gains recognized in income from available-for-sale debt and other securities, trading debt securities and equity securities	$ 5	$ 13	$ 0

Impairment Loss, Debt Securities, Portion Recognized in Earnings

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Amount of unrealized and 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 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) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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