Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.14)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

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-Name Regulation S-X (SX)

-Number 210

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Property and Equipment (Details) (USD $)	3 Months Ended		9 Months Ended
Property and Equipment (Details) (USD $)	Apr. 25, 2015	Apr. 26, 2014	Apr. 25, 2015	Apr. 26, 2014	Jul. 26, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 614,702,000us-gaap_PropertyPlantAndEquipmentGross		$ 614,702,000us-gaap_PropertyPlantAndEquipmentGross		$ 558,710,000us-gaap_PropertyPlantAndEquipmentGross
Less: accumulated depreciation	(388,374,000)		(388,374,000)		(353,297,000)
Property and equipment, net	226,328,000us-gaap_PropertyPlantAndEquipmentNet		226,328,000us-gaap_PropertyPlantAndEquipmentNet		205,413,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense	19,800,000us-gaap_Depreciation	18,600,000us-gaap_Depreciation	57,800,000us-gaap_Depreciation	55,700,000us-gaap_Depreciation
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	3,408,000		3,408,000		3,408,000
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	11,655,000		11,655,000		11,589,000
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	6,950,000		6,950,000		5,335,000
Vehicles
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	308,887,000		308,887,000		279,631,000
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	84,235,000		84,235,000		73,349,000
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	8,244,000		8,244,000		7,790,000
Equipment and machinery
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 191,323,000		$ 191,323,000		$ 177,608,000
Minimum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			10 years
Minimum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			1 year
Minimum \| Vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			1 year
Minimum \| Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			3 years
Minimum \| Office furniture and equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			2 years
Minimum \| Equipment and machinery
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			1 year
Maximum \| Buildings
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			35 years
Maximum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			10 years
Maximum \| Vehicles
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			5 years
Maximum \| Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			10 years
Maximum \| Office furniture and equipment
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			7 years
Maximum \| Equipment and machinery
Property, Plant and Equipment [Line Items]
Estimated Useful Lives			10 years