COMMITMENTS AND CONTINGENCIES 2 (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended				1 Months Ended		3 Months Ended
	Oct. 31, 2008 subsidiary	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Minimum	Mar. 31, 2013 Maximum	Jul. 31, 2011 Infineon Litigation patent	Apr. 30, 2011 Infineon Litigation patent	Mar. 31, 2012 Infineon Litigation patent	Dec. 28, 2012 Infineon Litigation patent
Contingencies
Number of patents claimed to be infringed							11
Number of Infineon patents alleged to be either invalid or not infringed							3
Number of Infineon patents Atmel is seeking to declare either invalid or not infringed						11
Number of Atmel patents counterclaimed that Infineon infringed on						6
Number of additional Infineon patents claimed to be infringed by the company								4
Number of patents withdrawn									4
Number of company's French subsidiaries where inspection conducted by European Union Commission	1
Product Warranties
Product Warranty Period				30 days	3 years
Activity related to the product warranty liability
Balance at beginning of period		$ 4,832	$ 5,746
Accrual for warranties during the period, net of change in estimates		487	1,287
Actual costs incurred		(690)	(1,309)
Balance at end of period		$ 4,629	$ 5,724