Pension and Savings Plans - Plan's Funded Status (Detail) - USD ($) $ in Thousands	4 Months Ended	12 Months Ended
Aug. 25, 2018	Aug. 25, 2018	Aug. 26, 2017
Change in Projected Benefit Obligation:
Projected benefit obligation at beginning of year		$ 314,724
Interest cost		10,356	$ 10,335
Actuarial (gains) losses		(676)
Annuities purchased		(157,589)
Benefits and settlements paid		(166,815)
Benefit obligations at end of year			314,724
Change in Plan Assets:
Fair value of plan assets at beginning of year		316,267
Actual return on plan assets		(3,428)
Employer contributions	11,400	11,596
Annuities purchased		(157,589)
Benefits and settlements paid		(166,815)
Asset reversion upon termination		(31)
Fair value of plan assets at end of year			$ 316,267

Defined benefit plan annuities purchased.

No definition available.

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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

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Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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

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Amount of increase in benefit obligation for benefits provided to employees payable from defined benefit plan or payable upon retirement.

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