Consolidated Statements of Income - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Operating Revenues
Operating revenues	$ 8,425.5	$ 5,566.5	$ 5,669.4
Operating Expenses
Compensation and benefits	2,971.3	1,873.9	1,584.7
Sales, distribution and marketing	2,105.8	1,703.1	1,819.6
Information systems and technology	486.1	288.4	258.5
Occupancy	218.1	147.9	133.6
Amortization of intangible assets	232.0	54.0	14.7
General, administrative and other	537.2	450.3	391.4
Total operating expenses	6,550.5	4,517.6	4,202.5
Operating Income	1,875.0	1,048.9	1,466.9
Other Income (Expenses)
Investment and other income (losses), net	264.7	(38.4)	141.4
Interest expense	(85.4)	(33.4)	(22.4)
Other income (expenses), net	569.2	(31.0)	180.9
Income before taxes	2,444.2	1,017.9	1,647.8
Taxes on income	349.6	230.8	442.3
Net income	2,094.6	787.1	1,205.5
Less: net income (loss) attributable to
Redeemable noncontrolling interests	94.1	48.6	6.2
Nonredeemable noncontrolling interests	169.3	(60.4)	3.6
Net Income Attributable to Franklin Resources, Inc.	$ 1,831.2	$ 798.9	$ 1,195.7
Earnings per Share
Basic	$ 3.58	$ 1.59	$ 2.35
Diluted	$ 3.57	$ 1.59	$ 2.35
Consolidated Investment Products [Member]
Other Income (Expenses)
Investment and other income (losses), net	$ 421.1	$ 70.2	$ 78.8
Expenses of consolidated investment products	(31.2)	(29.4)	(16.9)
Less: net income (loss) attributable to
Redeemable noncontrolling interests	63.8	45.0
Investment management fees [Member]
Operating Revenues
Operating revenues	6,541.6	3,981.7	3,985.2
Sales and distribution fees [Member]
Operating Revenues
Operating revenues	1,635.5	1,362.0	1,444.6
Shareholder servicing fees [Member]
Operating Revenues
Operating revenues	211.2	195.1	216.3
Other [Member]
Operating Revenues
Operating revenues	$ 37.2	$ 27.7	$ 23.3