Fair Value Measurements, Gains (Losses) on Assets with Nonrecurring Fair Value Adjustments (Details) - Nonrecurring [Member] - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	$ (63)	$ (761)
Loans held for sale [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	1	8
Loans [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	(393)	(486)
Loans [Member] \| Total Commercial [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	(197)	(273)
Loans [Member] \| Total Consumer [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	(196)	(213)
Equity securities [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	344	(249)
Other assets class [Member]
Fair Value Assets And Liabilities Measured On Nonrecurring Basis Increase (Decrease) [Line Items]
Total	$ (15)	$ (34)