Stockholders' Equity (Details) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Summary of company's stock option activity
Options, Outstanding, Beginning Balance	4,644
Options, Outstanding, Granted	900
Options, Outstanding, Exercised	(49)
Options, Outstanding. Expired	(39)
Options, Outstanding, Forfeited	(103)
Options, Outstanding, Ending Balance	5,353