Selected Condensed Consolidating Financial Statements of Parent, Issuer, Guarantors and Non-Guarantors - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities:
Net cash provided by (used for) operating activities	$ 1,339.0	$ 1,399.6
Investing activities:
Capital expenditures	(860.2)	(976.8)
Cash paid related to business combinations, net of cash acquired		(3,368.3)
Investment in unconsolidated entities	(1.0)	(10.4)
Proceeds from sale of property, plant and equipment	22.5	108.3
Proceeds from property, plant and equipment insurance settlement	2.4	16.5
Other, net	10.9	30.0
Net cash used for investing activities	(825.4)	(4,200.7)
Financing activities:
Proceeds from issuance of notes	598.6	2,498.2
Additions to revolving credit facilities	413.0	192.2
Repayments of revolving credit facilities	(478.2)	(177.2)
Additions to debt	683.1	4,441.0
Repayments of debt	(1,195.8)	(4,665.0)
(Repayments) additions to commercial paper, net	(9.3)	445.6
Other debt (repayments) additions, net	(69.2)	45.9
Issuances of common stock, net of related minimum tax withholdings	16.7	8.6
Purchases of common stock		(88.6)
Cash dividends paid to stockholders	(292.6)	(350.7)
Cash distributions paid to noncontrolling interests	(1.4)	(3.4)
Other, net	(17.0)	(7.1)
Net cash (used for) provided by financing activities	(352.1)	2,339.5
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(21.6)	3.9
Increase (decrease) in cash, cash equivalents and restricted cash	139.9	(457.7)
Cash, cash equivalents and restricted cash at beginning of period	151.6	636.8
Cash, cash equivalents and restricted cash at end of period	291.5	179.1
Parent [Member]
Operating activities:
Net cash provided by (used for) operating activities	275.9	430.7
Investing activities:
Intercompany capital investment		(563.0)
Net cash used for investing activities		(563.0)
Financing activities:
Issuances of common stock, net of related minimum tax withholdings	16.7	8.6
Purchases of common stock		(88.6)
Cash dividends paid to stockholders	(292.6)	(350.7)
Intercompany capital receipt		563.0
Net cash (used for) provided by financing activities	(275.9)	132.3
Issuer [Member]
Operating activities:
Net cash provided by (used for) operating activities	(38.1)	(512.4)
Investing activities:
Intercompany notes proceeds		9.2
Intercompany capital investment		(563.0)
Net cash used for investing activities		(553.8)
Financing activities:
Proceeds from issuance of notes	598.6	2,498.2
Additions to revolving credit facilities	350.0	67.2
Repayments of revolving credit facilities	(350.0)	(67.2)
Additions to debt		4,101.8
Repayments of debt	(500.0)	(2,187.1)
(Repayments) additions to commercial paper, net	(9.3)	445.6
Other debt (repayments) additions, net	(46.0)	35.3
Intercompany notes payments		(3,800.0)
Other, net	(5.2)	(27.8)
Net cash (used for) provided by financing activities	38.1	1,066.0
Increase (decrease) in cash, cash equivalents and restricted cash		(0.2)
Cash, cash equivalents and restricted cash at beginning of period		0.2
Guarantor Subsidiaries [Member]
Operating activities:
Net cash provided by (used for) operating activities	250.6	445.9
Investing activities:
Capital expenditures		(2.5)
Proceeds from sale of property, plant and equipment	0.1
Intercompany notes issued		(0.1)
Intercompany notes proceeds	5.0	4.3
Other, net	9.9	28.2
Net cash used for investing activities	15.0	29.9
Financing activities:
Additions to debt		(1.0)
Repayments of debt	(105.0)	(958.6)
Intercompany notes borrowing		75.7
Intercompany notes payments		(70.2)
Net cash (used for) provided by financing activities	(105.0)	(954.1)
Increase (decrease) in cash, cash equivalents and restricted cash	160.6	(478.3)
Cash, cash equivalents and restricted cash at beginning of period	17.8	490.8
Cash, cash equivalents and restricted cash at end of period	178.4	12.5
Non-Guarantor Subsidiaries [Member]
Operating activities:
Net cash provided by (used for) operating activities	850.6	1,035.4
Investing activities:
Capital expenditures	(860.2)	(974.3)
Cash paid related to business combinations, net of cash acquired		(3,368.3)
Investment in unconsolidated entities	(1.0)	(10.4)
Proceeds from sale of property, plant and equipment	22.4	108.3
Proceeds from property, plant and equipment insurance settlement	2.4	16.5
Intercompany notes issued		(75.7)
Intercompany notes proceeds		3,870.2
Other, net	1.0	1.8
Net cash used for investing activities	(835.4)	(431.9)
Financing activities:
Additions to revolving credit facilities	63.0	125.0
Repayments of revolving credit facilities	(128.2)	(110.0)
Additions to debt	683.1	340.2
Repayments of debt	(590.8)	(1,519.3)
Other debt (repayments) additions, net	(23.2)	10.6
Cash distributions paid to noncontrolling interests	(1.4)	(3.4)
Intercompany notes borrowing		0.1
Intercompany notes payments	(5.0)	(13.5)
Intercompany capital receipt		563.0
Other, net	(11.8)	20.7
Net cash (used for) provided by financing activities	(14.3)	(586.6)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(21.6)	3.9
Increase (decrease) in cash, cash equivalents and restricted cash	(20.7)	20.8
Cash, cash equivalents and restricted cash at beginning of period	133.8	145.8
Cash, cash equivalents and restricted cash at end of period	113.1	166.6
Eliminations [Member]
Investing activities:
Intercompany notes issued		75.8
Intercompany notes proceeds	(5.0)	(3,883.7)
Intercompany capital investment		1,126.0
Net cash used for investing activities	(5.0)	(2,681.9)
Financing activities:
Intercompany notes borrowing		(75.8)
Intercompany notes payments	5.0	3,883.7
Intercompany capital receipt		(1,126.0)
Net cash (used for) provided by financing activities	$ 5.0	$ 2,681.9