Selected Balance Sheet Accounts (Details 4) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accrued expenses and other current liabilities
Accrued employee-related benefits	$ 1,934	$ 3,125
Other accrued expenses	555	1,346
Amounts due to customers	375	424
Other current liabilities	366	434
Total other accrued expenses and other current liabilities	1,296	2,204
Total accrued expenses and other current liabilities	$ 3,230	$ 5,329