Contingencies - Additional Information (Detail) (USD $)	9 Months Ended		12 Months Ended	9 Months Ended	1 Months Ended			9 Months Ended		9 Months Ended			9 Months Ended				9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Dec. 29, 2013	Sep. 28, 2014 Power Integrations LegalMatter	Jan. 31, 2011 POWI 1	Dec. 31, 2008 POWI 1	Oct. 31, 2006 POWI 1	Sep. 28, 2014 POWI 1 Product Claim Phase Patent	Oct. 20, 2004 POWI 1 Patent	Sep. 28, 2014 POWI 2 Claim Patent	Apr. 27, 2012 POWI 2 Power Integrations Patent	Apr. 27, 2012 POWI 2 System General Patent	Sep. 28, 2014 POWI 3 Subsidiary Patent	Sep. 28, 2014 POWI 4 Subsidiary Vendor	May 01, 2012 Powi5 Patent	May 01, 2012 Powi5 Power Integrations Patent	Sep. 28, 2014 Minimum POWI 1	Sep. 28, 2014 Maximum POWI 1
Loss Contingencies [Line Items]
Number of outstanding proceedings with power integrations				5
Number of patents in lawsuit								4	4	3	4	2	3		3	5
Number of phases in trial								3
Number of products in violation								33
Number of claims in lawsuit								7		1
Damages awarded for infringement of the patents			$ 30,000,000		$ 12,200,000	$ 6,100,000	$ 34,000,000						$ 105,000,000				$ 500,000	$ 750,000
Release of litigation charge	4,400,000	(12,600,000)						12,600,000
Number of patents infringed											2	1	2
Number of company entities included in complaint													2	4
Number of vendors included in lawsuit														7
Assessed damages for infringement of Fairchild patents														17,000,000
Product sales value			20,000
Possible losses, minimum	2,500,000
Possible losses, maximum	$ 18,900,000