Acquisitions and Divestitures (Uzbekistan Asset Purchase) (Details) - USD ($) $ in Millions		12 Months Ended
May 25, 2023	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Asset Acquisition [Line Items]
Financing receivables		$ 1,000.0	$ 1,220.2
Financing receivables progress payments		61.9	403.0	$ 665.1
Natural Gas-To-Syngas Processing Facility
Asset Acquisition [Line Items]
Price of acquisition	$ 1,000.0
Term Of Project Agreement (in years)	15 years
Financing receivables		1,000.0	920.0
Financing receivables progress payments		$ 62.0	$ 120.0	$ 600.0

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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The cash outflow for the purchase of amounts due from customers, clients, lessees, borrowers, or others under the terms of its agreements therewith.

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