Consolidated Statements of Comprehensive Income (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
Consolidated Statements of Comprehensive Income (Loss) [Abstract]
Net income (loss)	$ (1,312)	$ 9,908	$ (4,679)	$ 29,012
Other comprehensive income (loss):
Unrealized gain (loss) on investments, net of tax		4	42	(18)
Unrealized gain (loss) on currency translation	(1)	(1)	(4)	(2)
Other comprehensive income (loss)	(1)	3	38	(20)
Comprehensive income (loss)	$ (1,313)	$ 9,911	$ (4,641)	$ 28,992