Deferred Revenue (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013 Customers	Dec. 31, 2012 Customers
Deferred Revenue (Textual)
Deferred fees	$ 3,479	$ 2,725
Prepayments from future license fees [Member]
Deferred Revenue (Textual)
Deferred fees	2,500	2,100
Number of customer	3
Deferred engineering development fees [Member]
Deferred Revenue (Textual)
Deferred fees	$ 1,000	$ 600
Number of customer	17	13