Pension and Savings Plans - Additional Information (Detail) - USD ($) $ in Thousands	4 Months Ended	12 Months Ended
Aug. 25, 2018	Aug. 29, 2020	Aug. 31, 2019	Aug. 25, 2018
Pension and Savings Plans
Consecutive years of highest compensation used to determine defined benefit pension plan benefits		5 years
Annual contributions by the Company to pension plans	$ 11,400
Pension termination charges (refund)	$ 130,300	$ 0	$ (6,796)	$ 130,263
Periodic pension benefit expense		$ 0
Percentage of company matching retirement savings plan contributions that vest immediately		100.00%
Percentage of savings option up to qualified earnings		25.00%
Annual contribution by employer towards 401(k) Plan		$ 29,800	$ 25,800	$ 23,100

Number of consecutive years of highest compensation used to determine defined benefit pension plan benefits.

No definition available.

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- Definition

Maximum percentage of qualified earnings that can be contributed to the savings plan.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

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

+ References

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-Publisher FASB
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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ Details

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- Definition

Amount of cash outflow for other postretirement benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes pension benefit.

+ References

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- Definition

Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

+ References

No definition available.

+ Details

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- Definition

Amount of noncash expense (reversal of expense) for pension benefits. Excludes other postretirement benefits.

+ References

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