Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	60,000	60,000
Common stock, shares issued	32,975	30,768
Common stock, shares outstanding	32,975	30,768