Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Accrued Liabilities and Other Liabilities [Abstract]
Accrued employee compensation	$ 3,542	$ 3,585
Deferred rent	217	213
Accrued legal expense	919	334
Accrued consulting expense	0	134
Accrued vendor charges	781	692
Accrued revenue share expense	859	932
Accrued patent settlement and license costs	0	500
Accrued clinical trial expense	267	302
Accrued other	910	1,119
Total	$ 7,495	$ 7,811