Fair Value Assumptions, Qualitative Assessments, Asset Percent

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- Definition

Fair Value Assumptions, Terminal Growth Rate

+ References

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- Definition

Number of Reporting Units that Exceeded Carrying Value

+ References

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

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-Name Accounting Standards Codification

-Topic 820

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

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- Definition

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

+ References

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- Definition

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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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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Goodwill and Intangible Assets (Details) (USD $)	3 Months Ended	9 Months Ended		12 Months Ended
Goodwill and Intangible Assets (Details) (USD $)	Apr. 25, 2015	Apr. 25, 2015	Apr. 26, 2014	Jul. 26, 2014	Oct. 25, 2014	Jan. 24, 2015
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Goodwill	$ 269,465,000us-gaap_Goodwill	$ 269,465,000us-gaap_Goodwill		269,088,000us-gaap_Goodwill
Amortization expense for finite-lived intangible assets	4,100,000us-gaap_AmortizationOfIntangibleAssets	12,400,000us-gaap_AmortizationOfIntangibleAssets	14,100,000us-gaap_AmortizationOfIntangibleAssets
Goodwill
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Reporting units as a percent of consolidated goodwill balance				20.00%
Discount rate				11.50%
Fair value assumptions, expected term				7 years
Minimum \| Goodwill
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Terminal growth rate range				1.50%
Maximum \| Goodwill
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Terminal growth rate range				3.00%
Businesses Acquired in Fiscal 2013
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Number of Reporting Units that Exceeded Carrying Value				3
Excess carrying value, percent				25.00%
First Reporting Unit Acquired in Fiscal 2013
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Goodwill				10,600,000
Second Reporting Unit Acquired in Fiscal 2013
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Goodwill				4,800,000
Third Reporting Unit Acquired in Fiscal 2013
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Goodwill				3,600,000
Hewitt Power & Communications, Inc
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Carrying amount					5,900,000
Customer relationships
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Carrying amount	179,859,000	179,859,000		173,594,000		400,000
Customer relationships \| Hewitt Power & Communications, Inc
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Carrying amount	5,900,000	5,900,000
Contract backlog
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Carrying amount	8,076,000	8,076,000		15,285,000
Contract backlog \| Hewitt Power & Communications, Inc
Finite-Lived and Indefinite-Lived Intangible Assets [Line Items]
Carrying amount	$ 7,200,000	$ 7,200,000