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Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

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-Publisher FASB

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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Acquisitions (Details) (USD $)	3 Months Ended
Acquisitions (Details) (USD $)	Jan. 24, 2015	Oct. 25, 2014	Apr. 26, 2014	Jul. 26, 2014
Business Acquisition [Line Items]
Goodwill	$ 269,465,000us-gaap_Goodwill			$ 269,088,000us-gaap_Goodwill
Property, Plant and Equipment, Gross	586,561,000us-gaap_PropertyPlantAndEquipmentGross			558,710,000us-gaap_PropertyPlantAndEquipmentGross
Connect Cable Contractors, Inc. and Systems Communications Services, Inc. [Member] [Member]
Business Acquisition [Line Items]
Acquisition payments	1,500,000
Hewitt Power & Communications, Inc
Business Acquisition [Line Items]
Acquisition payments		8,000,000
Finite-Lived Intangible Assets, Gross		5,900,000
Telecommunications Specialty Construction Contractor, Canada
Business Acquisition [Line Items]
Acquisition payments			700,000
Watts Brothers
Business Acquisition [Line Items]
Acquisition payments				16,400,000
Goodwill		1,600,000
Finite-Lived Customer Relationships, Gross		8,500,000
Property, Plant and Equipment, Gross		$ 3,700,000