Shareholders' Equity - Schedule Of Stock Reserved For Future Issuance (Details) - shares	Dec. 31, 2016	Dec. 31, 2015
Common Stock
Common shares reserved for future issuance	3,800,153	4,233,243
Exercise of outstanding stock options
Common Stock
Common shares reserved for future issuance	285,999	461,050
Future granting of option and stock awards
Common Stock
Common shares reserved for future issuance	2,421,120	2,642,346
Future stock purchases through ESPP
Common Stock
Common shares reserved for future issuance	197,066	233,879
Tarp Warrant
Common Stock
Common shares reserved for future issuance	895,968	895,968