Income Taxes - Narrative (Details) (USD $)	9 Months Ended
Oct. 26, 2014	Jan. 26, 2014
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%
Percentage of uncertain tax positions evaluating criteria	50.00%
Gross unrecognized tax benefits	$ 9,901,000	$ 14,414,000
Net tax benefits, if recognized, would impact the effective tax rate	7,800,000	12,300,000
Unrecognized tax benefits, interest and penalties	$ 293,000	$ 293,000

Percentage of uncertain tax positions evaluating criteria

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

+ References

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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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.

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

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-Name Accounting Standards Codification

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