Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
May 31, 2020	May 31, 2019	May 31, 2020	May 31, 2019
Accumulated other comprehensive income
Balance	$ 282,117	$ 255,635	$ 271,227	$ 246,756
Total other comprehensive (loss) income	(885)	(1,408)	767	(351)
Balance	291,493	263,356	291,493	263,356
Restricted investments, other comprehensive gains (losses) before reclassifications, tax benefit				4
Restricted investments, other comprehensive gains (losses) before reclassifications, tax expense			11
Change in funded status of pension plan, other comprehensive gains (losses) before reclassifications, tax (expense) benefit			0	0
Foreign currency translation adjustment, other comprehensive gains (losses) before reclassifications, tax (expense) benefit			0	0
Restricted investments, reclassifications to net income of previously deferred (gains) losses, tax (expense) benefit			8	1
Change in funded status of pension plan, reclassifications to net income of previously deferred (gains) losses, tax (expense) benefit			156	218
Foreign currency translation adjustment, reclassifications to net income of previously deferred (gains) losses, tax (expense) benefit			0	0
Accumulated Other Comprehensive Income (Loss)
Accumulated other comprehensive income
Balance	(14,060)	(11,279)	(14,324)	(12,336)
Other comprehensive gains (losses) before reclassifications			347	(968)
Reclassifications to net income of previously deferred (gains) losses			420	617
Adoption of ASU 2018-02	(1,388)		(1,388)
Total other comprehensive (loss) income			767	(351)
Balance	(14,945)	(12,687)	(14,945)	(12,687)
Restricted investments
Accumulated other comprehensive income
Balance			154	126
Other comprehensive gains (losses) before reclassifications			29	(12)
Reclassifications to net income of previously deferred (gains) losses			(24)	(1)
Total other comprehensive (loss) income			5	(13)
Balance	159	113	159	113
Change in funded status of pension plans
Accumulated other comprehensive income
Balance			(6,271)	(5,796)
Reclassifications to net income of previously deferred (gains) losses			444	618
Adoption of ASU 2018-02	(1,388)		(1,388)
Total other comprehensive (loss) income			444	618
Balance	(7,215)	(5,178)	(7,215)	(5,178)
Foreign currency translation adjustment
Accumulated other comprehensive income
Balance			(8,207)	(6,666)
Other comprehensive gains (losses) before reclassifications			318	(956)
Total other comprehensive (loss) income			318	(956)
Balance	$ (7,889)	$ (7,622)	$ (7,889)	$ (7,622)

Represents the restricted investment tax amount before reclassifications

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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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