Common Stock (Schedule Of Authorized But Unissued Common Stock) (Details) In Thousands, unless otherwise specified	Dec. 31, 2011
Class of Stock [Line Items]
Total	11,518
2007 Equity Incentive Plan [Member]
Class of Stock [Line Items]
Total	7,529
2007 Employee Stock Purchase Plan [Member]
Class of Stock [Line Items]
Total	92
Amended And Restated 2007 Non-Employee Directors Stock Option Plan [Member]
Class of Stock [Line Items]
Total	591
Amended And Restated Directors Deferred Compensation Plan [Member]
Class of Stock [Line Items]
Total	197
Exercise Of Warrants [Member]
Class of Stock [Line Items]
Total	3,109