Fair Value Measurements and Disclosures (Details) (USD $) In Thousands, unless otherwise specified	Aug. 03, 2013	Feb. 02, 2013	Jul. 28, 2012
Carrying Amount [Member]
Summary of company's financial instruments
Cash and cash equivalents	$ 27,773	$ 42,279	$ 146,470
Short-term investments	51,948	67,694
Long-term tenant allowance receivables	1,005	960	917
Carrying Amount [Member] | Cash [Member]
Summary of company's financial instruments
Cash and cash equivalents	18,540	5,612	32,134
Carrying Amount [Member] | Money Market Funds [Member]
Summary of company's financial instruments
Cash and cash equivalents	9,233	36,667	114,336
Carrying Amount [Member] | Certificates of Deposit [Member]
Summary of company's financial instruments
Short-term investments	7,613	5,053
Carrying Amount [Member] | US Treasury Securities [Member]
Summary of company's financial instruments
Short-term investments	9,991	19,991
Carrying Amount [Member] | US Government Securities [Member]
Summary of company's financial instruments
Short-term investments	34,344	42,650
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member]
Summary of company's financial instruments
Short-term investments		0
Long-term tenant allowance receivables	0	0	0
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member] | Cash [Member]
Summary of company's financial instruments
Cash and cash equivalents	18,540	5,612	32,134
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member] | Money Market Funds [Member]
Summary of company's financial instruments
Cash and cash equivalents	0	0	0
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member] | Certificates of Deposit [Member]
Summary of company's financial instruments
Short-term investments	0	0
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member] | US Treasury Securities [Member]
Summary of company's financial instruments
Short-term investments	0	0
Level 1 [Member] | Fair Value Measurements at Reporting Date [Member] | US Government Securities [Member]
Summary of company's financial instruments
Short-term investments	0	0
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member]
Summary of company's financial instruments
Short-term investments		0
Long-term tenant allowance receivables	0	0	0
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member] | Cash [Member]
Summary of company's financial instruments
Cash and cash equivalents	0	0	0
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member] | Money Market Funds [Member]
Summary of company's financial instruments
Cash and cash equivalents	9,233	36,667	114,336
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member] | Certificates of Deposit [Member]
Summary of company's financial instruments
Short-term investments	7,596	5,047
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member] | US Treasury Securities [Member]
Summary of company's financial instruments
Short-term investments	9,999	19,991
Level 2 [Member] | Fair Value Measurements at Reporting Date [Member] | US Government Securities [Member]
Summary of company's financial instruments
Short-term investments	34,319	42,592
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member]
Summary of company's financial instruments
Short-term investments		0
Long-term tenant allowance receivables	1,005	960	917
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member] | Cash [Member]
Summary of company's financial instruments
Cash and cash equivalents	0	0	0
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member] | Money Market Funds [Member]
Summary of company's financial instruments
Cash and cash equivalents	0	0	0
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member] | Certificates of Deposit [Member]
Summary of company's financial instruments
Short-term investments	0	0
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member] | US Treasury Securities [Member]
Summary of company's financial instruments
Short-term investments	0	0
Level 3 [Member] | Fair Value Measurements at Reporting Date [Member] | US Government Securities [Member]
Summary of company's financial instruments
Short-term investments	$ 0	$ 0