Exit and Other Related Liabilities - Activity in Exit and Other Related Liabilities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended	42 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2024
TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	$ 54
Amounts recognized in expense	3	$ 10		$ 391
Costs paid or otherwise settled	(11)
Balance at end of period	43		$ 43	43
TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense		10		308
Other
Restructuring Reserve [Roll Forward]
Balance at beginning of period	234
Amounts recognized in expense	(28)		467
Costs paid or otherwise settled	(200)
Balance at end of period	3		3	3
Other | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(31)		261
Investor Services Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Adjustments	25
Investor Services Employee Compensation and Benefits | TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	42
Amounts recognized in expense	3	8		309
Costs paid or otherwise settled	(9)
Balance at end of period	33		33	33
Investor Services Employee Compensation and Benefits | TD Ameritrade Integration | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	0	8		243
Investor Services Employee Compensation and Benefits | TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense		8		243
Investor Services Employee Compensation and Benefits | TD Ameritrade Integration | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense		8		243
Investor Services Employee Compensation and Benefits | Other
Restructuring Reserve [Roll Forward]
Balance at beginning of period	171
Amounts recognized in expense	(21)		344
Costs paid or otherwise settled	(146)
Balance at end of period	2		2	2
Investor Services Employee Compensation and Benefits | Other | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(23)		191
Investor Services Employee Compensation and Benefits | Other | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(23)		191
Investor Services Employee Compensation and Benefits | Other | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(23)		191
Advisor Services Employee Compensation and Benefits
Restructuring Reserve [Roll Forward]
Adjustments	8
Advisor Services Employee Compensation and Benefits | TD Ameritrade Integration
Restructuring Reserve [Roll Forward]
Balance at beginning of period	12
Amounts recognized in expense	0	2		82
Costs paid or otherwise settled	(2)
Balance at end of period	10		10	10
Advisor Services Employee Compensation and Benefits | TD Ameritrade Integration | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	0	2		65
Advisor Services Employee Compensation and Benefits | TD Ameritrade Integration | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense		2		65
Advisor Services Employee Compensation and Benefits | TD Ameritrade Integration | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense		$ 2		65
Advisor Services Employee Compensation and Benefits | Other
Restructuring Reserve [Roll Forward]
Balance at beginning of period	63
Amounts recognized in expense	(7)		123
Costs paid or otherwise settled	(54)
Balance at end of period	1		1	$ 1
Advisor Services Employee Compensation and Benefits | Other | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(8)		70
Advisor Services Employee Compensation and Benefits | Other | Compensation and benefits
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	(8)		70
Advisor Services Employee Compensation and Benefits | Other | Compensation and benefits | Employee Severance And Retention
Restructuring Reserve [Roll Forward]
Amounts recognized in expense	$ (8)		$ 70