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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Effective tax rate (as a percent)	22.40%	31.30%
Federal statutory rate (as a percent)	21.00%	21.00%
Income tax credits and incentives	$ 10.9	$ 7.4
Tax expense related to nondeductible costs		5.6
Tax expense related to Foreign residual income	7.2	4.0
Tax expense related to state income taxes	4.5	$ 2.8
Gross book-tax differences from non-U.S. subsidiaries	$ 1,500.0

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- Definition

Amount of gross book tax differences of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to repatriation of foreign earnings.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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