SEGMENT AND GEOGRAPHIC INFORMATION - Revenue and Income (Loss) From Operations (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 business_unit segment	Dec. 31, 2012 segment	Dec. 31, 2011
Segment Reporting Information [Line Items]
Number of reportable segments	2	1
Number of business units	4
Revenue	$ 330,399	$ 295,623	$ 267,474
Income (loss) from operations	(12,552)	(39,091)	(16,641)
Affymetrix Core [Member]
Segment Reporting Information [Line Items]
Revenue	252,164	258,612	267,474
Income (loss) from operations	528	(30,299)	(16,641)
eBioscience [Member]
Segment Reporting Information [Line Items]
Revenue	78,235	37,011	0
Income (loss) from operations	$ (13,080)	$ (8,792)	$ 0