Schedule II Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
Balance at Beginning of Period	$ 233	$ 213
Expense (Recovery)	3	20
Deductions	(25)
Balance at End of Period	211	233
SEC Schedule, 12-09, Reserve, Warranty [Member]
Balance at Beginning of Period	346	233
Expense (Recovery)	243	452
Deductions	(255)	(339)
Balance at End of Period	$ 334	$ 346