Benefits and Pension Plans - Future Benefit Payments (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Estimated future pension benefit payments
2021	$ 2,996
2022	1,759
2023	2,507
2024	1,948
2025	1,788
2026-2030	5,393
Employer contribution	$ 1,864	$ 1,570	$ 2,085

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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