Income Taxes Income Taxes - Repatriation of Foreign Earnings (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Undistributed Earnings of Foreign Subsidiaries	$ 383.5	$ 354.7
Foreign Earnings Repatriated	$ 13.0

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

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