Note 7 - Obligations and Funded Status Related to Its Pension Plans and SERP (Details) - USD ($) $ in Thousands	12 Months Ended
Aug. 27, 2016	Aug. 29, 2015	Aug. 30, 2014
Pension Plan [Member]
Projected benefit obligation	$ 8,479	$ 8,755
Service cost	204	192	$ 172
Interest cost	307	294	328
Amendments		263
Actuarial loss (gain)	506	(228)
Benefits paid	(370)	(314)
Settlements	(126)	(483)
Projected benefit obligation	9,000	8,479	8,755
Fair value of plan assets	4,757	5,008
Actual return on plan assets	71	153
Employer contributions	420	394
Settlements	(125)	(484)
Fair value of plan assets	4,753	4,757	5,008
Funded status (net amount recognized):	(4,247)	(3,722)
Supplemental Executive Retirement Plan [Member]
Projected benefit obligation	23,755	21,284
Service cost	819	821	615
Interest cost	984	1,133	942
Amendments
Actuarial loss (gain)	5,568	290
Benefits paid	(430)	(243)
Settlements
Projected benefit obligation	30,696	23,755	21,284
Fair value of plan assets
Actual return on plan assets
Employer contributions
Settlements
Fair value of plan assets
Funded status (net amount recognized):	$ (30,696)	$ (23,285)

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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Amount of contributions made by the employer to defined benefit plans.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts.

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Amount of plan assets that relate to an irrevocable action that relieves the employer, or plan, of primary responsibility for a benefit obligation and eliminates risks related to the obligation and the assets used to effect settlement. Includes, but is not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified pension benefits and purchasing annuity contracts to cover vested benefits.

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