EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Income for basic earnings per common share:
Net income	$ 355	$ 169	$ 667	$ 437
Less allocation of earnings and dividends to participating securities	0	0	(1)	(1)
Net income attributable to RJF common shareholders	355	169	666	436
Income for diluted earnings per common share:
Net income	355	169	667	437
Less allocation of earnings and dividends to participating securities	0	0	(1)	(1)
Net income attributable to RJF common shareholders	$ 355	$ 169	$ 666	$ 436
Common shares:
Average common shares in basic computation (in shares)	137.8	138.4	137.3	138.4
Dilutive effect of outstanding stock options and certain restricted stock units (in shares)	3.4	2.7	3.1	2.9
Average common shares used in diluted computation (in shares)	141.2	141.1	140.4	141.3
Earnings per common share:
Basic (in dollars per share)	$ 2.58	$ 1.22	$ 4.85	$ 3.15
Diluted (in dollars per share)	$ 2.51	$ 1.20	$ 4.74	$ 3.09
Stock options and certain restricted stock units excluded from weighted-average diluted common shares because their effect would be antidilutive (in shares)	0.1	0.7	0.2	0.6
Dividends per common share declared and paid: [Abstract]
Dividends per common share - declared (in dollars per share)	$ 0.39	$ 0.37	$ 0.78	$ 0.74
Dividends per common share - paid (in dollars per share)	$ 0.39	$ 0.37	$ 0.76	$ 0.71