Joint Venture (Other Income Related JV) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Schedule Of Equity Method Investments [Line Items]
Other income	$ 15,580	$ 12,932	$ 3,339
Woodward and General Electric Joint Venture [Member]
Schedule Of Equity Method Investments [Line Items]
Other income	$ 15,580	$ 12,932	$ 3,339

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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