Convertible Preferred Stock Warrants (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 12, 2004 investors
Convertible Preferred Stock: Warrants [Abstract]
Preferred Stock Investors				4
Warrant Strike Price				$ 6.95
Warrants outstanding	$ 0
Increase Decrease In Fair Value Of Common Stock Warrants	$ 0	$ 0	$ 451,000