Stock-Based Compensation - Summary of the Activity for Performance Unit Awards (Details) (Performance shares [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Apr. 28, 2013	Jan. 27, 2013
Units
Beginning balance (in shares)	353
Performance units granted (in shares)	186
Performance units vested (in shares)	(114)
Performance units cancelled/forfeited (in shares)	(13)
Ending balance (in shares)	412	353
Weighted Average Grant Date Fair Value (per share)
Beginning balance (in dollars per share)	$ 23.50
Performance units granted (in dollars per share)	$ 30.82
Performance units vested (in dollars per share)	$ 16.68
Performance units forfeited (in dollars per share)	$ 25.70
Ending balance (in dollars per share)	$ 28.62	$ 23.50
Aggregate Unrecognized Compensation
Beginning balance	$ 4,754
Ending balance	8,514	4,754
Weighted Average Period Over Which Expected to be Recognized (in years)
Weighted average period over which expected to be recognized	2 years	1 year 1 month
Subject To Share Settlement [Member]
Units
Beginning balance (in shares)	181
Performance units granted (in shares)	93
Performance units vested (in shares)	(57)
Performance units cancelled/forfeited (in shares)	(7)
Ending balance (in shares)	210
Subject To Cash Settlement [Member]
Units
Beginning balance (in shares)	172
Performance units granted (in shares)	93
Performance units vested (in shares)	(57)
Performance units cancelled/forfeited (in shares)	(6)
Ending balance (in shares)	202
Recorded Liability
Beginning balance	4,422
Change in liability	(2,859)
Ending balance	$ 1,563

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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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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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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