Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.005	$ 0.005
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.005	$ 0.005
Common stock, shares authorized	160,000,000	80,000,000
Common stock, shares issued	45,182,114	44,730,445
Common stock, shares outstanding	45,182,114	44,730,445