Retirement Plans (Schedule of Amounts Recognized in Balance Sheet) (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Compensation And Retirement Disclosure [Abstract]
Benefit obligation at beginning of year	$ 6,404	$ 6,825
Interest cost	246	243	$ 236
Actuarial (gain) loss	439	(134)
Benefits paid	(530)	(530)
Benefit obligation at end of year	$ 6,559	$ 6,404	$ 6,825

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

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