Quarterly report pursuant to Section 13 or 15(d)

Warranty (Details)

v3.8.0.1
Warranty (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Warranty [Abstract]    
Product warranty period 5 years  
Beginning balance $ 603 $ 600
Amounts charged (credited) to expense 79 (5)
Actual warranty costs paid (25) (14)
Ending balance $ 657 $ 581