Goodwill (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Goodwill
Goodwill			$ 5,880
Accumulated impairment losses			(965)
Goodwill [Roll Forward]
Net carrying value, beginning of period	$ 4,919	$ 4,915
Acquisition activity		4
Sale of business	(1)
Net carrying value, end of period	4,918	4,919
Operating Segments | Commercial Banking
Goodwill
Goodwill			3,074
Accumulated impairment losses			(750)
Goodwill [Roll Forward]
Net carrying value, beginning of period	2,324	2,324
Acquisition activity		0
Sale of business	0
Net carrying value, end of period	2,324	2,324
Operating Segments | Consumer and Small Business Banking
Goodwill
Goodwill			2,580
Accumulated impairment losses			(215)
Goodwill [Roll Forward]
Net carrying value, beginning of period	2,369	2,365
Acquisition activity		4
Sale of business	0
Net carrying value, end of period	2,369	2,369
Operating Segments | Wealth and Asset Management
Goodwill
Goodwill			226
Accumulated impairment losses			0
Goodwill [Roll Forward]
Net carrying value, beginning of period	226	226
Acquisition activity		0
Sale of business	(1)
Net carrying value, end of period	225	226
General Corporate and Other
Goodwill
Goodwill			0
Accumulated impairment losses			$ 0
Goodwill [Roll Forward]
Net carrying value, beginning of period	0	0
Acquisition activity		0
Sale of business	0
Net carrying value, end of period	$ 0	$ 0