Employee Equity Incentive Plans (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Stock-based compensation expense	$ 878	$ 1,270
Selling, General and Administrative Expenses [Member]
Stock-based compensation expense	809	1,162
Research and Development Expense [Member]
Stock-based compensation expense	$ 69	$ 108