Stock-Based Compensation - Narrative (Details) - USD ($)		12 Months Ended
	Feb. 26, 2014	Jan. 31, 2016	Jan. 25, 2015	Jan. 26, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefit realized from option exercise activity		$ 5,900,000	$ 0	$ 12,800,000
Potential per share consideration due upon change in control		$ 40.00
Number of employees affected by modification of awards		12
Incremental cost related to modification of awards		$ 0
Performance unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value units granted (in dollars per share)		$ 28.60	$ 24.74	$ 30.82
Market Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value units granted (in dollars per share)		$ 0.00
Employee stock unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Weighted average fair value units granted (in dollars per share)		$ 20.79	$ 23.90	$ 30.95
Minimum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Maximum | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Subject to Cash Settlement | Performance unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase (decrease) in liability		$ (1,654,000)	$ 586,000	$ (3,117,000)
Subject to Cash Settlement | Non-employee director stock unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Increase (decrease) in liability		$ (1,344,000)	$ 1,233,000	$ (576,000)
Vested but unsettled stock units		175,132
Share-based compensation liability, long-term		$ 3,000,000
Weighted average fair value units granted (in dollars per share)		$ 19.70	$ 26.59	$ 35.17
Subject To Share Settlement | Non-employee director stock unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Weighted average fair value units granted (in dollars per share)		$ 19.70
Individuals Not Associated With EnVerv Transaction [Member] | Performance unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance condition, highest potential performance level		200.00%
Maximum number of shares which would be settled in shares		363,032
Remaining value of shares which would be settled in cash		363,032
Target performance metrics for performance unit awards, fiscal year 2016		58.00%
Target performance metrics for performance unit awards, fiscal year 2015		0.00%
Chief Executive Officer [Member] | Tranche One | Market Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, terms of award	The award is eligible to vest during the period commencing February 26, 2014 and ending February 26, 2019 (the “Performance Period”) as follows: 30% of the restricted stock units covered by the award will vest if, during any consecutive 120 calendar day period that commences and ends during the Performance Period, the average per-share closing price of the Company’s common stock equals or exceeds $35.00 (“Tranche 1”) and the award will vest in full if, during any consecutive 120 calendar day period that commences and ends during the Performance Period, the average per-share closing price of the Company’s common stock equals or exceeds $40.00 (“Tranche 2”). The award will also vest if a majority change in control of the Company occurs during the Performance Period and, in connection with such event, the Company’s stockholders become entitled to receive per-share consideration having a value equal to or greater than $40.00.
Percentage of award that will vest upon satisfaction of performance condition	30.00%
Minimum closing share price used to determine market condition	$ 35.00
Weighted average fair value units granted (in dollars per share)		$ 17.26	17.26
Chief Executive Officer [Member] | Tranche Two | Market Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of award that will vest upon satisfaction of performance condition	100.00%
Minimum closing share price used to determine market condition	$ 40.00
Weighted average fair value units granted (in dollars per share)		$ 14.88	$ 14.88