FAIR VALUE MEASUREMENTS (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Aug. 02, 2012
Fair value measurements
Transfers of assets between the fair value measurement levels	$ 0	$ 0
GSTA
Fair value measurements
Period over which monthly payment of agreed upon percentage of acquisition and renewal revenue is required to be paid	5 years	5 years	5 years
Period over which the projected amount would have been received by the marketing partner if the prior marketing agreement was extended	5 years	5 years	5 years
Contingent consideration			(3,000)
Recurring | Amount
Fair value measurements
Contingent consideration	(1,961)	(2,693)
Recurring | Significant Unobservable Inputs (Level 3)
Fair value measurements
Contingent consideration	$ (1,961)	$ (2,693)