Stock-Based Compensation - Summary of Activity for Market Performance Units (Details) (Market Performance RSUs, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Jan. 25, 2015	Jan. 26, 2014
Market Performance RSUs
Number of Units
Beginning balance (in shares)	0
Stock units granted (in shares)	220
Stock units vested (in shares)	0
Stock units forfeited (in shares)	0
Ending balance (in shares)	220	0
Weighted Average Grant Date Fair Value (per share)
Beginning balance (in dollars per share)	$ 0.00
Weighted average fair value units granted (in dollars per share)	$ 15.59
Stock units vested (in dollars per share)	$ 0.00
Stock units forfeited (in dollars per share)	$ 0.00
Ending balance (in dollars per share)	$ 15.59	$ 0.00
Aggregate Unrecognized Compensation
Beginning balance	$ 0
Ending balance	$ 0	$ 0
Weighted Average Remaining Expense Period (in years)
Ending Balance	1 year 2 months	0 years

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Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB

-Name Accounting Standards Codification

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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