MARKETABLE SECURITIES - Gross unrealized gains (losses) on marketable securities (Details 1) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized Gains	$ 182	$ 332
Gross unrealized (Losses)	(152)	(20)
Municipal Obligations
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized Gains	174	284
Gross unrealized (Losses)	(152)	(20)
Corporate Obligations
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized Gains	8	48
Gross unrealized (Losses)