Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	2 Months Ended	3 Months Ended	4 Months Ended	6 Months Ended	12 Months Ended
	Feb. 28, 2018	Feb. 28, 2018	Dec. 31, 2017	Feb. 28, 2018	Aug. 31, 2019	Aug. 31, 2018
Operating Loss Carryforwards [Line Items]
Statutory federal corporate tax rate	21.00%		35.00%
Tax benefit due to remeasurement of deferred tax assets and liabilities		$ 34.3		$ 34.3
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense				$ 11.5
Scenario, Forecast
Operating Loss Carryforwards [Line Items]
Statutory federal corporate tax rate					21.00%	25.70%
Maximum
Operating Loss Carryforwards [Line Items]
Statutory federal corporate tax rate	25.70%
Transition tax payable period				8 years