Employee and Retiree Benefits Changes in Postretirement Health Care Liability (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 26, 2017	Aug. 27, 2016
Retirement Benefits [Abstract]
Balance at beginning of year	$ 6,346
Interest cost	29	$ 327
Service cost	16	108
Net benefits paid	53
Plan amendment	(6,338)
Balance at end of year	$ 0	$ 6,346

No definition available.

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

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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

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