LEGAL PROCEEDINGS (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012
LEGAL PROCEEDINGS [Abstract]
Significant Costs Incurred in Connection With Administrative Proceedings	$ 0

Legal expenses incurred in connection with intellectual property and patents.

No definition available.

Name:	affx_LegalExpensesAssociatedWithAdministrativeProceedings
Namespace Prefix:	affx_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration