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

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Amount of income tax benefit for remeasurement of deferred tax liability from change in tax rate pursuant to Tax Cuts and Jobs Act.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Amount of income tax expense (benefit) for remeasurement of deferred tax from change in tax rate pursuant to Tax Cuts and Jobs Act.

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Amount of reasonable estimate for income tax benefit for which accounting for tax effect for remeasurement of deferred tax liability from change in tax rate is incomplete pursuant to Tax Cuts and Jobs Act.

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Income Taxes - Tax Act (Details) - USD ($) $ in Millions	8 Months Ended	9 Months Ended	12 Months Ended	28 Months Ended
Income Taxes - Tax Act (Details) - USD ($) $ in Millions	Dec. 31, 2017	Jan. 31, 2018	Apr. 30, 2019	Apr. 30, 2020
Income Taxes
Federal statutory rate (as a percent)	35.00%			21.00%
Provisional income tax benefit			$ 6.7
Decrease from provisional amount		$ (1.1)
Income tax benefit related to tax adjustment			$ 0.1