Postretirement and Other Employee Benefits (Benefit Obligations and Plan Assets, Changes in Benefit Obligation and Plan Assets and Funded Status of Plans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Change in projected benefit obligation
Beginning projected benefit obligation	$ 161,104	$ 167,714
Service cost	1,437	1,063	$ 1,068
Interest cost	3,715	3,807	2,942
Actuarial loss (gain)	19,060	(6,019)
Curtailments gain	0	(998)
Total benefits paid	(6,568)	(6,211)
Plan participants’ contributions	35	31
Amendments	0	1,864
Acquisitions	6,040	0
Effect of conversion to U.S. dollars	(10,133)	(147)
Ending projected benefit obligation	174,690	161,104	167,714
Change in plan assets
Beginning fair value of plan assets	151,715	146,698
Actual return on plan assets	19,784	8,146
Employer contributions	1,717	1,811
Benefits paid from plan assets	(5,435)	(4,758)
Plan participants’ contributions	35	31
Effect of conversion to U.S. dollars	(9,715)	(213)
Ending fair value of plan assets	158,101	151,715	$ 146,698
Unfunded status	(16,589)	(9,389)
Amounts recognized in the Consolidated Balance Sheets
Accrued benefit liability, current	368	428
Accrued benefit liability, noncurrent	16,221	8,961
Accumulated other comprehensive loss
Actuarial loss, before tax	24,343	22,387
Prior service cost, before tax	690	$ 719
Net actuarial loss expected to be amortized to net period benefit cost in next fiscal year	800
Prior service cost expected to be amortized to net periodic benefit cost in next fiscal year	$ 0