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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits	$ 1.2			$ 1.2				$ 3.3
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	24.50%		21.00%	24.50%	35.00%
Weighted Average Deferred Income Tax Provision Rate			25.00%			39.00%
Tax Cuts and Jobs Act, Income Tax Expense (Benefit)					$ 42.5
Transition Tax Expense									$ 7.5
Transition Tax True-up							$ 0.6
Transition Tax Liability	$ 6.4			$ 6.4

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Expense associated with 2017 US Federal tax reform referred to as "Transition Tax" associated with unrepatriated foreign earnings.

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Transition Tax Liability

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Transition Tax True-up

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The weighted average of the tax rates used to provide deferred tax assets or liabilities for temporary differences based on when the underlying differences are expected to turn.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income tax expense (benefit) from effect of Tax Cuts and Jobs Act.

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Amount of unrecognized tax benefits.

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