Income Taxes (Details) - USD ($)		3 Months Ended	6 Months Ended	12 Months Ended
	Feb. 28, 2018	Feb. 28, 2018	Feb. 28, 2018	Aug. 31, 2019	Aug. 31, 2018
Income Tax Contingency [Line Items]
Provisional tax liability			$ 0
Discrete provisional net benefit	$ 136,800,000
Deferred tax benefit		$ 41,300,000
Scenario, Forecast
Income Tax Contingency [Line Items]
Corporate Tax Rate				21.00%	25.70%