Share-Based Compensation (Details) $ in Millions	3 Months Ended
Nov. 30, 2017 USD ($) company shares
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	252,865.00
Vesting term	5 years
Vesting percentage per year	20.00%
Shares granted, fair value \| $	$ 7
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	246,161
Performance Shares \| Total Shareholder Return (TSR)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	119,763.00
Shares granted, fair value \| $	$ 3
Total Shareholder Return Designated Peer Group \| company	16
Performance Shares \| Total Shareholder Return (TSR) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Based Awards Award Payouts Threshold	50.00%
Performance Shares \| Total Shareholder Return (TSR) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Based Awards Award Payouts Threshold	200.00%
Performance Shares \| Return on Capital Employed (ROCE)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	126,398.00
Shares granted, fair value \| $	$ 3
Performance period	3 years
Performance Shares \| Return on Capital Employed (ROCE) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Based Awards Award Payouts Threshold	50.00%
Performance Shares \| Return on Capital Employed (ROCE) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Based Awards Award Payouts Threshold	200.00%

Performance Based Awards Award Payouts Threshold

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Total Fair Value

+ References

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- Definition

TSR Designated Peer Group

+ References

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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