Income Taxes - Narrative (Details) (USD $)	3 Months Ended
Apr. 26, 2015	Jan. 25, 2015
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%
Percentage of uncertain tax positions evaluating criteria	50.00%
Gross unrecognized tax benefit before federal impact of state items	$ 9,800,000	$ 9,900,000
Net tax benefits, if recognized, would impact the effective tax rate	7,600,000	7,800,000
Unrecognized tax benefits, interest and penalties	$ 293,000	$ 293,000

Gross Unrecognized Tax Benefit Before Federal Impact Of State Items

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- Definition

Percentage of uncertain tax positions evaluating criteria

+ References

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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

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-Name Accounting Standards Codification

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