SEGMENT INFORMATION, Information Concerning Operations (Details) £ in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) businessSegment	Jun. 30, 2021 USD ($)	Jun. 30, 2022 GBP (£)	Jan. 21, 2022 USD ($)	Sep. 30, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | businessSegment			5
Revenues:
Total net revenues	$ 2,718	$ 2,471	$ 8,172	$ 7,065
Pre-tax income
Total pre-tax income	415	385	1,406	1,231
Net interest income (expense):
Net interest income	314	165	706	493
Total assets:
Total assets	86,111		86,111				$ 61,891
Goodwill:
Goodwill	1,335		1,335				660
Charles Stanley
Goodwill:
Goodwill	147		147		£ 121	$ 164
Operating segments | Private Client Group
Revenues:
Total net revenues	1,958	1,696	5,719	4,810
Pre-tax income
Total pre-tax income	251	195	659	527
Net interest income (expense):
Net interest income	58	29	122	84
Total assets:
Total assets	25,729		25,729				20,270
Goodwill:
Goodwill	564		564				417
Operating segments | Capital Markets
Revenues:
Total net revenues	383	446	1,410	1,331
Pre-tax income
Total pre-tax income	61	115	349	349
Net interest income (expense):
Net interest income	3	1	8	5
Total assets:
Total assets	2,169		2,169				2,457
Goodwill:
Goodwill	173		173				174
Operating segments | Asset Management
Revenues:
Total net revenues	228	225	698	629
Pre-tax income
Total pre-tax income	93	105	303	275
Net interest income (expense):
Net interest income	1	0	1	0
Total assets:
Total assets	546		546				476
Goodwill:
Goodwill	69		69				69
Operating segments | Bank
Revenues:
Total net revenues	276	169	656	496
Pre-tax income
Total pre-tax income	74	104	259	286
Net interest income (expense):
Net interest income	270	161	636	473
Total assets:
Total assets	55,562		55,562				36,154
Goodwill:
Goodwill	529		529				0
Operating segments | Other
Revenues:
Total net revenues	(21)	2	(54)	(6)
Pre-tax income
Total pre-tax income	(64)	(134)	(164)	(206)
Net interest income (expense):
Net interest income	(18)	(26)	(61)	(69)
Total assets:
Total assets	2,105		2,105				$ 2,534
Intersegment eliminations
Revenues:
Total net revenues	$ (106)	$ (67)	$ (257)	$ (195)