The period of time for the carryback of federal net operating losses per the CARES Act.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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- Definition

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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Amount of unrecognized tax benefits.

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Income Taxes (Details) - USD ($) $ in Millions					1 Months Ended	3 Months Ended			6 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jul. 01, 2020	Apr. 01, 2020	Mar. 27, 2020	Mar. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Income taxes
Effective tax rate (as a percent)							18.50%	24.00%	20.20%	23.50%
Unrecognized tax liability							$ 12.6		$ 12.6		$ 14.1
Anticipated decrease in income tax contingency reserves in the next 12 months							$ 0.5		$ 0.5
Carryback period for Federal Net Operating Losses per the CARES Act				5 years
UK
Income taxes
Statutory corporation tax rate (as a percentage)		17.00%	17.00%		19.00%				19.00%
UK \| Forecast
Income taxes
Statutory corporation tax rate (as a percentage)	19.00%
UK \| Forecast \| Minimum
Income taxes
Adjustment to deferred tax assets and liabilities						$ 6.0
UK \| Forecast \| Maximum
Income taxes
Adjustment to deferred tax assets and liabilities						$ 9.0