Debt And Capital Lease Obligations (Capital Lease And Financing Obligations) (Narrative) (Details) - USD ($)	12 Months Ended
Sep. 01, 2018	Sep. 02, 2017
Capital Leased Assets [Line Items]
Amount due under capital leases and financing agreements	$ 27,926,000	$ 27,829,000
Property and equipment acquired under capital leases and financing agreements	442,000
Non-cash financing activity related to the capital lease	1,163,000
Amortization of capital leases	$ 0
Fulfillment Center [Member]
Capital Leased Assets [Line Items]
Capital lease term	20 years
Amount due under capital leases and financing agreements	$ 27,025,000	$ 27,025,000
Minimum [Member] \| Fulfillment Center [Member]
Capital Leased Assets [Line Items]
Capital lease, prepayment term with no penalty	7 years
Maximum [Member] \| Fulfillment Center [Member]
Capital Leased Assets [Line Items]
Capital lease, prepayment term with no penalty	20 years

Capital lease, prepayment term with no penalty

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- Definition

Lessee Leasing Arrangements, Capital Leases, Term of Contract

+ References

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.7-03(a)(16))
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- Definition

The increase during the period in capital lease obligations due to entering into new capital leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The charge for the use of long-lived depreciable capital leased assets for the period.

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