CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowances for doubtful accounts	$ 273	$ 428
Provision for obsolescence	$ 392	$ 439
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	34,312,527	33,847,100
Common stock, shares outstanding (in shares)	34,169,952	33,704,525