CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement of Comprehensive Income [Abstract]
Net loss	$ (5,502)	$ (3,584)	$ (20,863)	$ (41,629)
Other comprehensive income, net of tax:
Foreign currency translation adjustments	(180)	(119)	32	(192)
Unrealized gain on short-term investments, net of tax	254	(36)	134	(10)
Other comprehensive income, net of tax	74	(155)	166	(202)
Total comprehensive loss, net of tax	$ (5,428)	$ (3,739)	$ (20,697)	$ (41,831)