SUBSEQUENT EVENT (Details) (Stock repurchase, USD $) In Millions, unless otherwise specified	1 Months Ended
Apr. 30, 2012
Stock repurchase
Subsequent Events
Authorized additional amount under stock repurchase program	$ 200

The additional amount authorized by an entity's Board of Directors under a stock repurchase plan.

No definition available.

Name:	atml_StockRepurchaseProgramAuthorizedAdditionalAmount
Namespace Prefix:	atml_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration