FINANCIAL INSTRUMENTS (Details 2) (USD $) In Thousands, unless otherwise specified																	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Level 2	Dec. 31, 2012 Level 2	Dec. 31, 2013 Commercial Paper	Dec. 31, 2012 Commercial Paper	Dec. 31, 2013 Commercial Paper Level 2	Dec. 31, 2012 Commercial Paper Level 2	Dec. 31, 2013 Corporate Bonds	Dec. 31, 2012 Corporate Bonds	Dec. 31, 2013 Corporate Bonds Level 2	Dec. 31, 2012 Corporate Bonds Level 2	Dec. 31, 2013 Asset-backed Securities	Dec. 31, 2012 Asset-backed Securities	Dec. 31, 2013 Asset-backed Securities Level 2	Dec. 31, 2012 Asset-backed Securities Level 2	Dec. 31, 2013 Minimum	Dec. 31, 2013 Maximum	Dec. 31, 2013 Standard & Poor's, A Rating
Short-term investments
Short-term investments	$ 59,637	$ 30,924																	$ 59,600
Maturity period																	109 days	363 days
Amortized Cost	59,632	30,897			17,986	15,974			30,808	8,874			10,838	6,049
Gross Unrealized Gains	13	28			11	23			1	1			1	4
Gross Unrealized Losses	(8)	(1)			0	0			(7)	(1)			(1)	0
Fair Value			$ 59,637	$ 30,924			$ 17,997	$ 15,997			$ 30,802	$ 8,874			$ 10,838	$ 6,053