CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Net sales	$ 2,208.8	$ 1,580.8	$ 5,674.3	$ 5,072.6
Cost of sales	1,824.2	1,323.3	4,732.0	4,233.2
Gross income	384.6	257.5	942.3	839.4
Operating expenses:
Selling, general and administrative	177.6	137.6	495.0	468.4
Amortization of purchased intangibles	3.2	1.3	6.8	9.7
Total operating expenses	180.8	138.9	501.8	478.1
Operating income	203.8	118.6	440.5	361.3
Other income (expense):
Interest expense	(12.2)	(12.4)	(36.0)	(47.8)
Interest income	0.5	0.7	1.7	3.6
Miscellaneous, net	0.4	1.5	2.0	(4.7)
Income before income taxes and losses of unconsolidated affiliates	192.5	108.4	408.2	312.4
Provision for (benefit of) income taxes	(21.9)	28.0	24.5	87.0
Income before losses of unconsolidated affiliates	214.4	80.4	383.7	225.4
Equity in losses of unconsolidated affiliates	(0.5)	(0.2)	(0.7)	(0.9)
Net income	$ 213.9	$ 80.2	$ 383.0	$ 224.5
Earnings per share:
Basic	$ 3.11	$ 1.18	$ 5.59	$ 3.29
Diluted	3.07	1.17	5.53	3.26
Cash dividends declared per share on Common Stock	$ 0.33	$ 0.30	$ 0.99	$ 0.90