Accrued expenses and other current liabilities, other non-current expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accrued expenses and other current liabilities
Accruals for services provided by vendors-not yet billed	$ 3,804	$ 2,348
Personnel related accruals and liabilities	2,247	5,646
Other current liabilities	440	844
Total	6,491	8,838
Glybera
Accrued expenses and other current liabilities
Accrual for termination agreement, current portion	400	600
Accrual for termination agreement, non-current portion	$ 300	$ 300