Long-Term and Short-Term Financing Arrangements (Narrative) - USD ($) $ in Thousands				12 Months Ended
	Aug. 26, 2015	Jul. 27, 2015	Jul. 24, 2015	Feb. 03, 2018	Jan. 28, 2017	Jan. 30, 2016	May 11, 2011
Debt Instrument [Line Items]
Borrowings under revolving credit agreement				$ 0	$ 110,000
Cash payments of interest for financing arrangements				16,500	15,200	$ 11,900
Loss on early extinguishment of debt				0	0	(10,651)
Extinguishment of debt, non-cash						3,000
Line of Credit
Debt Instrument [Line Items]
Maximum Borrowing Capacity				600,000
Line of Credit Borrowing Capacity Increase Option				$ 150,000
Line of Credit Facility, Initiation Date				Dec. 18, 2014
Expiration date				Dec. 18, 2019
Facility Percentage of Borrowing Base Under Condition One				12.50%
Number of consecutive business days for borrowing base availability over minimum under condition one				30 days
Percentage Of Borrowing Base Under Condition Two				10.00%
Borrowing Base Availability Under Condition Two				$ 50,000
Fixed Charge Coverage Ratio				100.00%
Maximum amount of borrowings under either the Credit Agreement or Former Credit Agreement at the end of any month				$ 260,000	260,000
Average daily borrowings				$ 93,500	$ 34,800
Weighted average interest rate				2.50%	2.70%
Borrowings under revolving credit agreement				$ 0
Letters of credit outstanding under the Credit Agreement				10,400
Additional borrowing availability under Credit Agreement				$ 535,200
2019 Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount							$ 200,000
Debt instrument, interest rate							7.125%
Principal Amount Redeemed in Tender Offer	$ 39,300		$ 160,700
Debt Instrument, Redemption Price, Percentage	103.563%		103.95%
2023 Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount		$ 200,000
Debt instrument, interest rate		6.25%
Debt Instrument, Redemption Price, Percentage				101.00%
Proceeds from Issuance of Debt						$ 196,300
Debt instrument, maturity date		Aug. 15, 2023