Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Name:	us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Debt Interest Rates at Period End (Details)	9 Months Ended
Debt Interest Rates at Period End (Details)	Apr. 29, 2017	Apr. 23, 2016	Jul. 30, 2016
Standby Letters of Credit
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate at Period End	1.75%		2.00%
Credit Agreement - Term Loan (matures April 2020)
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate at Period End	2.74%		2.49%
Credit Agreement - Revolving facility (matures April 2020)
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate at Period End	3.48%		0.00%
Unutilized commitment fee (in percent)	0.35%	0.40%