Summary of Significant Accounting Policies - Stock option equivalents (Details) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	11,238	12,130
Options [Member]
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	2,204	2,596
Warrants [Member]
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	1,083	1,083
Option matching rights [Member]
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	1,276	1,809
Shares to be issued upon conversion of convertible of long-term loan, related party [Member]
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	6,575	6,575
Restricted stock [Member]
Summary of the approximate number of common stock equivalents outstanding
Total number of common stock equivalents outstanding	100	67