Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Accumulated other comprehensive income
Balance	$ 273,473	$ 248,193	$ 271,227	$ 246,756
Total other comprehensive (loss) income	(57)	1,448	1,652	1,057
Balance	282,117	255,635	282,117	255,635
Restricted investments, other comprehensive gains (losses) before reclassifications, tax benefit				5
Restricted investments, other comprehensive gains (losses) before reclassifications, tax expense			7
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			91	184
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	(14,003)	(12,727)	(14,324)	(12,336)
Other comprehensive gains (losses) before reclassifications			1,414	527
Reclassifications to net income of previously deferred (gains) losses			238	530
Adoption of ASU 2018-02	(1,388)		(1,388)
Total other comprehensive (loss) income			1,652	1,057
Balance	(14,060)	(11,279)	(14,060)	(11,279)
Restricted investments
Accumulated other comprehensive income
Balance			154	126
Other comprehensive gains (losses) before reclassifications			19	(11)
Reclassifications to net income of previously deferred (gains) losses			(21)	3
Total other comprehensive (loss) income			(2)	(8)
Balance	152	118	152	118
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			259	527
Adoption of ASU 2018-02	(1,388)		(1,388)
Total other comprehensive (loss) income			259	527
Balance	(7,400)	(5,269)	(7,400)	(5,269)
Foreign currency translation adjustment
Accumulated other comprehensive income
Balance			(8,207)	(6,666)
Other comprehensive gains (losses) before reclassifications			1,395	538
Total other comprehensive (loss) income			1,395	538
Balance	$ (6,812)	$ (6,128)	$ (6,812)	$ (6,128)

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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