REVENUES, Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Principal transactions	$ 137	$ 143	$ 432	$ 345
Noninterest income	2,306	1,659	6,572	5,248
All other	38	13	98	(3)
Interest income	205	217	608	799
Total revenues	2,511	1,876	7,180	6,047
Interest expense	(40)	(42)	(115)	(136)
Net revenues	2,471	1,834	7,065	5,911
Receivables related to contracts with customers	359		359		$ 342
Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1,262	867	3,502	2,828
Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	552	486	1,671	1,461
Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	415	343	1,239	1,116
Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	171	134	508	448
Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	113	88	320	288
Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	131	121	411	380
Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	161	134	465	484
Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	104	83	297	261
RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	18	20	58	129
Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	39	31	110	94
Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	276	139	779	428
Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	153	60	424	192
Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	80	42	229	146
Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	43	37	126	90
Total other
Disaggregation of Revenue [Line Items]
Noninterest income	55	33	155	47
Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	17	20	57	50
Operating segments | Private Client Group
Disaggregation of Revenue [Line Items]
Principal transactions	13	16	38	50
Noninterest income	1,667	1,222	4,726	4,052
All other	7	4	20	20
Interest income	31	31	91	125
Total revenues	1,698	1,253	4,817	4,177
Interest expense	(2)	(4)	(7)	(19)
Net revenues	1,696	1,249	4,810	4,158
Operating segments | Private Client Group | Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1,050	715	2,914	2,330
Operating segments | Private Client Group | Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	390	319	1,156	1,050
Operating segments | Private Client Group | Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	377	303	1,118	1,000
Operating segments | Private Client Group | Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	167	131	498	438
Operating segments | Private Client Group | Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	113	88	320	288
Operating segments | Private Client Group | Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	97	84	300	274
Operating segments | Private Client Group | Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	209	177	603	623
Operating segments | Private Client Group | Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	105	82	298	260
Operating segments | Private Client Group | RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	65	63	192	267
Operating segments | Private Client Group | Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	39	32	113	96
Operating segments | Private Client Group | Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	11	7	33	29
Operating segments | Private Client Group | Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Private Client Group | Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	11	7	33	29
Operating segments | Private Client Group | Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Private Client Group | Total other
Disaggregation of Revenue [Line Items]
Noninterest income	7	4	20	20
Operating segments | Private Client Group | Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Capital Markets
Disaggregation of Revenue [Line Items]
Principal transactions	125	127	394	298
Noninterest income	445	321	1,326	873
All other	1	0	5	4
Interest income	4	4	12	22
Total revenues	449	325	1,338	895
Interest expense	(3)	(2)	(7)	(14)
Net revenues	446	323	1,331	881
Operating segments | Capital Markets | Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1	1	3	4
Operating segments | Capital Markets | Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	160	166	509	411
Operating segments | Capital Markets | Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	35	39	115	113
Operating segments | Capital Markets | Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2	2	5	6
Operating segments | Capital Markets | Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Capital Markets | Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	33	37	110	107
Operating segments | Capital Markets | Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1	2	6	5
Operating segments | Capital Markets | Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Capital Markets | RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	1	1	1
Operating segments | Capital Markets | Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1	1	5	4
Operating segments | Capital Markets | Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	265	132	746	399
Operating segments | Capital Markets | Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	153	60	424	192
Operating segments | Capital Markets | Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	69	35	196	117
Operating segments | Capital Markets | Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	43	37	126	90
Operating segments | Capital Markets | Total other
Disaggregation of Revenue [Line Items]
Noninterest income	18	20	62	54
Operating segments | Capital Markets | Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	17	20	57	50
Operating segments | Asset Management
Disaggregation of Revenue [Line Items]
Principal transactions	0	0	0	0
Noninterest income	225	163	629	530
All other	1	1	2	2
Interest income	0	0	0	1
Total revenues	225	163	629	531
Interest expense	0	0	0	0
Net revenues	225	163	629	531
Operating segments | Asset Management | Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	218	157	607	510
Operating segments | Asset Management | Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	2	2	7	6
Operating segments | Asset Management | Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2	2	7	6
Operating segments | Asset Management | Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	2	2	7	6
Operating segments | Asset Management | Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4	3	13	12
Operating segments | Asset Management | Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	1	0	2
Operating segments | Asset Management | RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	4	2	13	10
Operating segments | Asset Management | Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | Asset Management | Total other
Disaggregation of Revenue [Line Items]
Noninterest income	1	1	2	2
Operating segments | Asset Management | Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank
Disaggregation of Revenue [Line Items]
Principal transactions	0	0	1	0
Noninterest income	8	9	23	20
All other	8	9	22	20
Interest income	172	181	505	635
Total revenues	180	190	528	655
Interest expense	(11)	(12)	(32)	(51)
Net revenues	169	178	496	604
Operating segments | RJ Bank | Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	0	0	1	0
Operating segments | RJ Bank | Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Operating segments | RJ Bank | Total other
Disaggregation of Revenue [Line Items]
Noninterest income	8	9	22	20
Operating segments | RJ Bank | Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations
Disaggregation of Revenue [Line Items]
Principal transactions	(1)	0	(1)	(3)
Noninterest income	(39)	(56)	(132)	(227)
All other	21	(1)	49	(49)
Interest income	(2)	1	0	16
Total revenues	(41)	(55)	(132)	(211)
Interest expense	(24)	(24)	(69)	(52)
Net revenues	(65)	(79)	(201)	(263)
Other and intersegment eliminations | Other and intersegment eliminations | Asset management and related administrative fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(7)	(6)	(22)	(16)
Other and intersegment eliminations | Other and intersegment eliminations | Total brokerage revenues
Disaggregation of Revenue [Line Items]
Noninterest income	0	(1)	(2)	(6)
Other and intersegment eliminations | Other and intersegment eliminations | Subtotal securities commissions
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1	(1)	(1)	(3)
Other and intersegment eliminations | Other and intersegment eliminations | Mutual and other fund products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	(1)	(2)	(2)
Other and intersegment eliminations | Other and intersegment eliminations | Insurance and annuity products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations | Equities, ETFs and fixed income products
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1	0	1	(1)
Other and intersegment eliminations | Other and intersegment eliminations | Total account and service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(53)	(48)	(157)	(156)
Other and intersegment eliminations | Other and intersegment eliminations | Mutual fund and annuity service fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(1)	0	(1)	(1)
Other and intersegment eliminations | Other and intersegment eliminations | RJBDP fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(47)	(44)	(135)	(139)
Other and intersegment eliminations | Other and intersegment eliminations | Client account and other fees
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	(5)	(4)	(21)	(16)
Other and intersegment eliminations | Other and intersegment eliminations | Total investment banking
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations | Merger & acquisition and advisory
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations | Equity underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations | Debt underwriting
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	0	0	0	0
Other and intersegment eliminations | Other and intersegment eliminations | Total other
Disaggregation of Revenue [Line Items]
Noninterest income	21	(1)	49	(49)
Other and intersegment eliminations | Other and intersegment eliminations | Tax credit fund revenues
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 0	$ 0	$ 0	$ 0