SEGMENT INFORMATION, Information Concerning Operations (Details) £ in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($) businessSegment	Mar. 31, 2021 USD ($)	Mar. 31, 2022 GBP (£)	Jan. 21, 2022 USD ($)	Jan. 21, 2022 GBP (£)	Sep. 30, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | businessSegment			5
Revenues:
Total net revenues	$ 2,673	$ 2,372	$ 5,454	$ 4,594
Pre-tax income
Total pre-tax income	433	447	991	846
Net interest income (expense):
Net interest income	204	163	392	328
Total assets:
Total assets	73,101		73,101					$ 61,891
Goodwill:
Goodwill	818		818					660
Charles Stanley
Goodwill:
Goodwill	159		159		£ 121	$ 164	£ 121
Operating segments | Private Client Group
Revenues:
Total net revenues	1,922	1,647	3,761	3,114
Pre-tax income
Total pre-tax income	213	192	408	332
Net interest income (expense):
Net interest income	34	27	64	55
Total assets:
Total assets	29,718		29,718					20,270
Goodwill:
Goodwill	575		575					417
Operating segments | Capital Markets
Revenues:
Total net revenues	413	433	1,027	885
Pre-tax income
Total pre-tax income	87	105	288	234
Net interest income (expense):
Net interest income	2	3	5	4
Total assets:
Total assets	2,358		2,358					2,457
Goodwill:
Goodwill	174		174					174
Operating segments | Asset Management
Revenues:
Total net revenues	234	209	470	404
Pre-tax income
Total pre-tax income	103	87	210	170
Total assets:
Total assets	462		462					476
Goodwill:
Goodwill	69		69					69
Operating segments | RJ Bank
Revenues:
Total net revenues	197	160	380	327
Pre-tax income
Total pre-tax income	83	111	185	182
Net interest income (expense):
Net interest income	189	155	366	312
Total assets:
Total assets	38,167		38,167					36,154
Operating segments | Other
Revenues:
Total net revenues	(18)	(12)	(33)	(8)
Pre-tax income
Total pre-tax income	(53)	(48)	(100)	(72)
Net interest income (expense):
Net interest income	(21)	(22)	(43)	(43)
Total assets:
Total assets	2,396		2,396					$ 2,534
Intersegment eliminations
Revenues:
Total net revenues	$ (75)	$ (65)	$ (151)	$ (128)