Condensed Consolidated Statements of Comprehensive Loss (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Condensed Consolidated Statements of Comprehensive Loss [Abstract]
Net loss	$ (5,473)	$ (14,567)	$ (16,645)	$ (27,929)
Unrealized (loss) gain on short-term investments	(1)	(3)	(2)	10
Comprehensive loss	$ (5,474)	$ (14,570)	$ (16,647)	$ (27,919)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

Net of tax amount of other comprehensive income (loss) attributable to the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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+ Details

- Definition

Before tax and reclassification adjustments amount of unrealized holding gain (loss) and transfers on available-for-sale securities.

+ References

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+ Details