Investments and Fair Value Measurement (Details Textual) (USD $) In Thousands, unless otherwise specified			3 Months Ended	6 Months Ended
Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Available-for-sale securities [Member]	Jun. 30, 2012 Available-for-sale securities [Member]
Investments and Fair Value Measurement (Textual) [Abstract]
Available-for-sale securities			$ 0	$ 0
Gross unrealized (losses)	(7)	(7)	0	0
Realized losses			0	0
Other-than-temporary impairments of available-for-sale securities			$ 0	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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