Subsequent Events (Details) (USD $)	3 Months Ended	9 Months Ended	1 Months Ended
Oct. 29, 2011	Oct. 30, 2010	Oct. 29, 2011	Oct. 30, 2010	Nov. 30, 2011 Dividend Declared
Subsequent Events
Cash dividend announced on common stock (in dollars per share)	$ 0.20	$ 0.16	$ 0.60	$ 0.48	$ 0.20

Aggregate dividends declared during the period for each share of common stock outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration