Summarized Financial Information of Equity Affiliates (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Schedule of Equity Method Investments [Line Items]
Dividends received from equity affiliates	$ 157.3	$ 107.0	$ 144.3
Investment in net assets of and advances to equity affiliates	1,649.3	1,432.2
Goodwill associated with affiliate companies accounted for by equity method	55.3	50.0
Proportionate share of accumulated dividend distribution taxes released per the India Finance Act		33.8
Obligation for future contribution to equity affiliate to be funded in next twelve months	150.0	94.4
Foreign affiliates
Schedule of Equity Method Investments [Line Items]
Investment in net assets of and advances to equity affiliates	$ 1,648.0	$ 1,431.3
Jazan Gas Projects Company
Schedule of Equity Method Investments [Line Items]
Ownership interest percentage	26.00%
Obligation for future contribution to equity affiliate to be funded in next twelve months	$ 94.4

The proportionate share of accumulated dividend distribution taxes released as a result of the India Finance Act.

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Amount of contractual obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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