Investments and Fair Value Measurement (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Investments and Fair Value Measurement (Textual) [Abstract]
Investments maturity period	1 year	1 year
Gross Unrealized (Losses)	$ (1)	$ (1)
Available-for-sale securities [Member]
Investments and Fair Value Measurement (Textual) [Abstract]
Gross Unrealized (Losses)	(1)	(1)
Realized losses	0	0
Other-than-temporary impairments of available-for-sale securities	$ 0	$ 0	$ 0