Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Expenses and Other Current Liabilities
Payroll and related costs	$ 10,382	$ 9,607
Employee benefits	6,097	5,281
Accrued warranty	3,941	3,662
Other	6,076	4,756
Accrued expenses and other current liabilities	$ 26,496	$ 23,306