Investment Securities - Gains and Losses Recognized in Income from Securities (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Available-for-sale debt and other securities:
Realized gains	$ 1	$ 4	$ 3	$ 34
Realized losses	0	0	0	(30)
Impairment losses	(5)	(4)	(10)	(4)
Net losses on available-for-sale debt and other securities	(4)	0	(7)	0
Trading debt securities:
Net realized losses	0	0	0	0
Net unrealized gains	0	2	0	2
Net trading debt securities gains	0	2	0	2
Equity securities:
Net realized gains	11	1	11	2
Net unrealized gains (losses)	(4)	4	9	7
Net equity securities gains	7	5	20	9
Total (losses) gains recognized in income from available-for-sale debt and other securities, trading debt securities and equity securities	3	7	13	11
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	$ 0	$ (1)	$ 2	$ 0

Total available for sale and trading securities gains losses.

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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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Amount of other-than-temporary impairment (OTTI) on investment in debt security, recognized in earnings.

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