Supplemental Information (Changes in Estimates) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Change in Accounting Estimate [Line Items]
Operating Income (Loss)	$ 459.8	$ 561.9	$ 1,111.8	$ 1,084.9
Contracts accounted for under percentage of completion
Change in Accounting Estimate [Line Items]
Operating Income (Loss)	$ (35.0)		$ (60.0)

The net result for the period of deducting operating expenses from operating revenues.

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-Publisher FASB
-Name Accounting Standards Codification
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