Prepaid Expenses, Accrued Expenses, Other Current Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Summary of prepaid expenses and other current assets
Prepaid insurance	$ 125	$ 27
Prepaid inventory purchases	158	1
Prepaid consulting & other	217	57
Total prepaid expenses and other current assets	$ 500	$ 85