SIGNIFICANT CUSTOMERS AND EXPORT SALES (Product Sales) (Details) (Sales Revenue, Goods, Net [Member])	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Minimum [Member] | Product Concentration Risk [Member] | Primary Low Power AC DC Power Conversion Products [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	97.00%	97.00%	97.00%	97.00%
Minimum [Member] | Other Product Families [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues			1.00%
Maximum [Member] | Product Concentration Risk [Member] | Primary Low Power AC DC Power Conversion Products [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	99.00%	99.00%	99.00%	99.00%
Maximum [Member] | Other Product Families [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues			3.00%
Product Concentration Risk [Member]
Revenue from External Customer [Line Items]
Number of primary groupings of low-power AC-DC power-conversion products	3	3	3	3
Product Concentration Risk [Member] | LinkSwitch [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	43.00%	39.00%	42.00%	37.00%
Product Concentration Risk [Member] | TinySwitch [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	33.00%	37.00%	33.00%	38.00%
Product Concentration Risk [Member] | TOPSwitch [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	21.00%	23.00%	23.00%	24.00%
Product Concentration Risk [Member] | Other Product Families [Member]
Revenue from External Customer [Line Items]
Concentration risk, percentage of total net revenues	3.00%	1.00%	2.00%	1.00%