Discontinued Operations (Details) (USD $)	9 Months Ended			3 Months Ended		12 Months Ended	3 Months Ended	12 Months Ended
	Jul. 30, 2011	Jul. 31, 2010	Sep. 30, 2007	Jan. 30, 2010 CPU Voltage Regulation And PC Thermal Monitoring Business [Member]	Aug. 02, 2008 CPU Voltage Regulation And PC Thermal Monitoring Business [Member]	Nov. 01, 2008 CPU Voltage Regulation And PC Thermal Monitoring Business [Member]	Jan. 30, 2010 Baseband Chipset Business [Member]	Oct. 31, 2009 Baseband Chipset Business [Member]	Nov. 01, 2008 Baseband Chipset Business [Member]	Jul. 30, 2011 Baseband Chipset Business [Member]
Amounts related to the CPU voltage regulation and PC thermal monitoring and Baseband Chipset Businesses, segregated from continuing operations and reported as discontinued operations [Abstract]
Gain on sale of discontinued operations before income taxes	$ 10,000,000	$ 1,316,000
Provision for income taxes	3,500,000	457,000
Gain on sale of discontinued operations, net of tax	6,500,000	859,000
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Amount placed In escrow						7,500,000
Additional proceeds released from escrow recorded as a pre-tax gain				1,000,000	6,600,000
Additional proceeds released from escrow, net of tax				600,000	3,800,000
One year manufacturing supply agreement						37,000,000
Liability related to manufacturing supply agreement						85,000,000
Additional cash payments related to sale of business								1,700,000
Amount placed into escrow and excluded from the gain calculations									10,000,000
Cash refund of foreign withholding tax							62,000,000
Additional pre-tax gain on sale							300,000
Additional gain on sale, net of tax							200,000
Additional proceeds the company may receive, currently held in escrow										10,000,000
Discontinued Operations (Textuals) [Abstract]
Refundable foreign withholding tax			$ 62,000,000