Income Taxes Accumulated Foreign Undistributed Earnings (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Mar. 31, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 393.9	$ 383.5
Foreign Earnings Repatriated	$ 30.0	$ 13.0

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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