Summary Of Significant Accounting Policies (Receivables, Net) (Detail) - USD ($) $ in Millions	Aug. 28, 2016	Aug. 30, 2015
Disclosure Summary Of Significant Accounting Policies Receivables Net [Abstract]
Vendor receivables	$ 755	$ 729
Reinsurance receivables	270	273
Third-party pharmacy receivables	99	103
Other receivables, net	128	119
Receivables, Net	$ 1,252	$ 1,224

Disclosure - Summary Of Significant Accounting Policies (Receivables, Net) [Abstract]

No definition available.

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- Definition

Receivables due from member's insurance companies for the amount above their co-pay, which is collected at the point-of-sale.

+ References

No definition available.

+ Details

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- Definition

Receivables due from vendors that may be used to settle related payables due to vendors.

+ References

No definition available.

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- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-06(3))
-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e604059-122996

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-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to and paid by the ceding insurer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21412-158489

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