Consolidated Statements of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Operating Revenues
Operating revenues	$ 2,152.8	$ 1,927.2	$ 4,143.9	$ 3,894.3
Operating Expenses
Compensation and benefits	1,028.2	847.3	1,996.5	1,826.5
Sales, distribution and marketing	484.3	406.6	885.1	795.2
Information systems and technology	155.1	128.0	286.1	249.4
Occupancy	76.2	59.7	142.9	114.2
Amortization of intangible assets	84.6	86.0	170.4	169.2
General, administrative and other	195.1	144.5	327.1	290.7
Total operating expenses	2,023.5	1,672.1	3,808.1	3,445.2
Operating Income	129.3	255.1	335.8	449.1
Other Income (Expenses)
Investment and other income, net	52.5	60.6	225.7	150.5
Interest expense	(27.7)	(33.5)	(46.5)	(64.4)
Expenses of consolidated investment products	1.0	2.2	3.0	9.8
Other income, net	108.8	110.9	233.5	144.8
Income before taxes	238.1	366.0	569.3	593.9
Taxes on income	62.8	92.9	137.7	153.2
Net income	175.3	273.1	431.6	440.7
Less: net income (loss) attributable to
Redeemable noncontrolling interests	42.8	83.2	52.3	81.7
Nonredeemable noncontrolling interests	8.3	(4.3)	3.8	(0.8)
Net income attributable to Franklin Resources, Inc.	$ 124.2	$ 194.2	$ 375.5	$ 359.8
Earnings per Share
Basic	$ 0.23	$ 0.38	$ 0.71	$ 0.70
Diluted	$ 0.23	$ 0.38	$ 0.71	$ 0.70
CIPs [Member]
Other Income (Expenses)
Investment and other income, net	$ 89.9	$ 87.2	$ 66.1	$ 73.6
Expenses of consolidated investment products	(5.9)	(3.4)	(11.8)	(14.9)
Less: net income (loss) attributable to
Redeemable noncontrolling interests	32.7	70.2	29.8	58.0
Investment management fees [Member]
Operating Revenues
Operating revenues	1,713.9	1,573.3	3,366.1	3,205.1
Sales and distribution fees [Member]
Operating Revenues
Operating revenues	358.3	301.4	654.7	593.3
Shareholder servicing fees [Member]
Operating Revenues
Operating revenues	68.0	43.3	100.5	76.7
Other [Member]
Operating Revenues
Operating revenues	$ 12.6	$ 9.2	$ 22.6	$ 19.2