CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018
CONSOLIDATED BALANCE SHEETS [Abstract]
Receivables, net of allowance for doubtful account	$ 120	$ 97
Other non-current assets, fair value of derivative instruments	3,611	4,364
Other long-term liabilities, fair value of derivative instruments	610	502
Other long-term liabilities, post-employment plans	$ 5,151	$ 4,715
Common stock, par value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	45,000,000	45,000,000
Common stock, shares issued	31,447,055	31,372,752
Common stock, shares outstanding	30,495,712	30,460,353
Treasury stock, shares	951,343	912,399

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of all derivative liabilities designated as fair value hedging instruments.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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