Goodwill And Intangible Assets (Impairment Charge Against Net Carrying Value Of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Oct. 30, 2011
Indefinite-lived Intangible Assets by Major Class [Line Items]
Net Carrying Amount	$ 2,470
Total Impairment	(2,470)
In-Process Research And Development [Member]
Indefinite-lived Intangible Assets by Major Class [Line Items]
Total Impairment	(2,470)
High-Speed Switching Technology For Power Management Applications [Member] | In-Process Research And Development [Member]
Indefinite-lived Intangible Assets by Major Class [Line Items]
Net Carrying Amount	2,070	[1]
Total Impairment	(2,070)	[1]
Integrated Driver For Telecommunications Applications [Member] | In-Process Research And Development [Member]
Indefinite-lived Intangible Assets by Major Class [Line Items]
Net Carrying Amount	400	[2]
Total Impairment	$ (400)	[2]

[1] related to the February 2009 Leadis Technology Inc. acquisition.

[2] related to the December 2009 Sierra Monolithics, Inc. acquisition.