Other Comprehensive (Loss) Income and Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
May 31, 2020	May 31, 2019	May 31, 2020	May 31, 2019	Aug. 31, 2019
Other Comprehensive (Loss) Income And Accumulated Other Comprehensive Loss [Abstract]
Foreign currency translation adjustments, pre-tax	$ (4,633)	$ (11,326)	$ 1,589	$ (15,804)
Foreign currency translation adjustments, net of tax	(4,633)	(11,326)	1,589	(15,804)
Net unrealized (loss) gain on cash flow hedges recognized in AOCL, pre-tax	(5,285)		(2,801)
Net unrealized (loss) gain on cash flow hedges recognized in AOCL, net of tax	(3,948)		(2,105)
Net unrealized (loss) gain on cash flow hedges recognized in AOCL, pre-tax		(225)		2,107
Net unrealized (loss) gain on cash flow hedges recognized in AOCL, net of tax		(160)		1,405
Other comprehensive loss, pre-tax	(9,918)	(11,551)	(1,212)	(13,697)
Other comprehensive loss, net of tax	(8,581)	$ (11,486)	(516)	$ (14,399)
Accumulated unrealized losses on cash flow hedges, net of tax	(4,371)		(4,371)		$ (2,266)
Accumulated foreign currency translation adjustments	(70,689)		(70,689)		(72,278)
Total accumulated other comprehensive loss	$ (75,060)		$ (75,060)		$ (74,544)

Other Comprehensive (Loss) Income And Accumulated Other Comprehensive Loss

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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