Borrowing Arrangements - Additional Information (Detail) (USD $)	6 Months Ended
	Jul. 29, 2012	Jul. 31, 2011
Debt Instrument [Line Items]
Amount of borrowings under credit facility during period	$ 0	$ 0
Amount outstanding under credit facility	0	0
Long-term debt obligations	7,073,000
Unsecured Revolving Line Of Credit
Debt Instrument [Line Items]
Credit facility, renewal date	Jun. 22, 2012
Current borrowing capacity	300,000,000
Additional borrowing capacity	200,000,000
Maximum borrowing capacity including additional borrowing capacity	500,000,000
Credit facility, maturity date	Jun. 22, 2017
Interest rate description	We may elect interest rates calculated at (i) Bank of America's prime rate (or, if greater, the average rate on overnight federal funds plus one-half of one percent, or a rate based on LIBOR plus one percent) plus a margin based on our leverage ratio, or (ii) LIBOR plus a margin based on our leverage ratio.
Unsecured Revolving Line Of Credit | LIBOR
Debt Instrument [Line Items]
Additional percentage over reference rate	1.00%
Unsecured Revolving Line Of Credit | Federal Funds
Debt Instrument [Line Items]
Additional percentage over reference rate	0.50%
Standby Letters of Credit
Debt Instrument [Line Items]
Amount issued but undrawn under credit facility	8,670,000
Unsecured Letter Of Credit Facilities
Debt Instrument [Line Items]
Additional percentage over reference rate	2.00%
Maximum borrowing capacity under letter of credit facilities including additional borrowing capacity	90,000,000
Letter of credit facilities, renewal date	Aug. 31, 2012
Letter of credit facilities, maturity date	Aug. 30, 2013
Latest expiration date possible for future letters of credit	Jan. 27, 2014
Outstanding letter of credit facilities	$ 21,890,000
Interest rate description	Interest on unreimbursed amounts under the letter of credit facilities accrues at the lender's prime rate (or if greater, the average rate on overnight federal funds plus one-half of one percent) plus 2.0%.
Unsecured Letter Of Credit Facilities | Federal Funds
Debt Instrument [Line Items]
Additional percentage over reference rate	0.50%