Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	3 Months Ended
Nov. 30, 2018	Nov. 30, 2017	Aug. 31, 2018	Feb. 28, 2017
Accounting Policies [Abstract]
Book Overdrafts	$ 35,000,000		$ 28,000,000
Accounts Receivable, Trade	189,000,000		164,000,000
Repayment of Advances With Scrap Metal	4,000,000	$ 3,000,000
Prepaid Expense	17,000,000		22,000,000
Insurance Receivable	16,000,000		36,000,000
Investment, Original Cost				$ 6,000,000
Cost Method Investments			6,000,000
Investment, Carrying Value	6,000,000
Cash, FDIC Insured Amount	250,000
Customer Issued Letters Of Credit	$ 84,000,000		$ 58,000,000

Letters of credit obtained from customers to guarantee payment of open accounts receivable as of the reporting date.

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- Definition

Noncash settlement of accounts receivable through inventory receipts, Amount

+ References

No definition available.

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- References

No definition available.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
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-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 45
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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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No definition available.

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Original amount of cost-method investments at the acquisition date.

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No definition available.

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- Definition

Amount of investment in equity security without readily determinable fair value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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- Definition

Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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-Name Accounting Standards Codification
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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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