Income Taxes [Line Items]

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- Definition

Operating loss carryforwards expirations period.

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- Definition

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

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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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- Definition

Tax year being audited in the income tax examination, in CCYY format.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Aug. 31, 2018	Feb. 28, 2018	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Income Taxes [Line Items]
Federal statutory rate			21.00%	25.70%	35.00%
Tax cut and jobs act of 2017 discrete income tax expense (benefit)		$ (7)		$ (37)
Effective tax rate			23.20%	(12.40%)	2.70%
Valuation allowance, deferred tax asset, increase (decrease), amount	$ (30)	$ (7)		$ (37)
Foreign Country
Income Taxes [Line Items]
Operating loss carryforwards			$ 16
Minimum
Income Taxes [Line Items]
Operating loss carryforwards expirations period			2019
Income tax examination, year under examination			2013
Minimum \| Foreign Country
Income Taxes [Line Items]
Operating loss carryforwards expirations period			2024
Maximum
Income Taxes [Line Items]
Operating loss carryforwards expirations period			2032
Income tax examination, year under examination			2018
Maximum \| Foreign Country
Income Taxes [Line Items]
Operating loss carryforwards expirations period			2039