Exit and Other Related Liabilities - Activity in Exit and Other Related Liabilities (Details) - USD ($) $ in Millions	12 Months Ended			39 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	$ 46	$ 35
Amounts recognized in expense	60	34	$ 108	$ 388
Costs paid or otherwise settled	(16)	(14)
Balance at end of period	54	46	35	54
TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	24	25	83	308
TD Ameritrade Integration | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	11	9	22	49
Other Restructuring Plan
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0
Amounts recognized in expense	495
Costs paid or otherwise settled	(58)
Balance at end of period	234	0		234
Other Restructuring Plan | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	292
Other Restructuring Plan | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	17
Investor Services | TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	36	28
Amounts recognized in expense	47	26	87	306
Costs paid or otherwise settled	(14)	(11)
Balance at end of period	42	36	28	42
Investor Services | TD Ameritrade Integration | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	20	19	66	243
Investor Services | TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	20	19	66	243
Investor Services | TD Ameritrade Integration | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	20	19	66	243
Investor Services | TD Ameritrade Integration | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	9	7	18	40
Investor Services | TD Ameritrade Integration | Occupancy and equipment | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	0	0	0	0
Investor Services | Other Restructuring Plan
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0
Amounts recognized in expense	365
Costs paid or otherwise settled	(43)
Balance at end of period	171	0		171
Investor Services | Other Restructuring Plan | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	214
Investor Services | Other Restructuring Plan | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	214
Investor Services | Other Restructuring Plan | Compensation and benefits | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	214
Investor Services | Other Restructuring Plan | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	13
Investor Services | Other Restructuring Plan | Occupancy and equipment | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	0
Advisor Services | TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	10	7
Amounts recognized in expense	13	8	21	82
Costs paid or otherwise settled	(2)	(3)
Balance at end of period	12	10	7	12
Advisor Services | TD Ameritrade Integration | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	4	6	17	65
Advisor Services | TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	4	6	17	65
Advisor Services | TD Ameritrade Integration | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	4	6	17	65
Advisor Services | TD Ameritrade Integration | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	2	2	4	9
Advisor Services | TD Ameritrade Integration | Occupancy and equipment | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	0	0	$ 0	0
Advisor Services | Other Restructuring Plan
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0
Amounts recognized in expense	130
Costs paid or otherwise settled	(15)
Balance at end of period	63	$ 0		$ 63
Advisor Services | Other Restructuring Plan | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	78
Advisor Services | Other Restructuring Plan | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	78
Advisor Services | Other Restructuring Plan | Compensation and benefits | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	78
Advisor Services | Other Restructuring Plan | Occupancy and equipment
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	4
Advisor Services | Other Restructuring Plan | Occupancy and equipment | Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	$ 0