Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 30, 2016	Jan. 31, 2015	Feb. 01, 2014
Available-for-sale securities
Amortized Cost	$ 3,015	$ 18,050
Unrealized Gains	1	5
Unrealized Losses	(1)	(10)
Available-for-sale Securities, Total	3,015	18,045
Purchases of available-for-sale securities	0	18,480	$ 24,484
Maturities of available-for-sale investments	14,987	16,506	$ 8,306
Other than temporary impairment of available-for-sale securities	0	0
Expected maturities of available-for-sale securities
Due in one year or less	3,015
Short Term Investments
Available-for-sale securities
Amortized Cost	3,015	13,293
Unrealized Gains	1	5
Unrealized Losses	(1)	(5)
Available-for-sale Securities, Total	3,015	13,293
Long-term investments
Available-for-sale securities
Amortized Cost		4,757
Unrealized Losses		(5)
Available-for-sale Securities, Total		4,752
Certificates of deposit \| Short Term Investments
Available-for-sale securities
Amortized Cost		4,080
Unrealized Losses		(2)
Available-for-sale Securities, Total		4,078
Commercial paper \| Short Term Investments
Available-for-sale securities
Amortized Cost		7,384
Unrealized Gains		3
Unrealized Losses		(3)
Available-for-sale Securities, Total		7,384
Corporate bonds \| Short Term Investments
Available-for-sale securities
Amortized Cost	2,810	1,615
Unrealized Gains	1	1
Unrealized Losses	(1)
Available-for-sale Securities, Total	2,810	1,616
Corporate bonds \| Long-term investments
Available-for-sale securities
Amortized Cost		2,857
Unrealized Losses		(4)
Available-for-sale Securities, Total		2,853
U.S. Agency securities \| Long-term investments
Available-for-sale securities
Amortized Cost		1,900
Unrealized Losses		(1)
Available-for-sale Securities, Total		1,899
Municipal bonds \| Short Term Investments
Available-for-sale securities
Amortized Cost	205	214
Unrealized Gains		1
Available-for-sale Securities, Total	$ 205	$ 215

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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