Overview and significant Accounting Policies (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance for doubtful accounts
Balance at beginning of year	$ 430	$ 697
Net charges to expense	351	131
Amounts recovered against the allowance	(115)	(398)
Balance at end of year	$ 666	$ 430