3. Allowance for Doubtful Accounts (Tables)

12 Months Ended

Dec. 31, 2017

Allowance For Doubtful Accounts Tables

Schedule of Allowance for Doubtful Accounts

	Years Ended December 31,
	2017		2016
Balance, beginning of year	$	50	$	49
Provision for doubtful accounts		—		17
Uncollectible accounts written off		—		(16	)
Balance, end of year	$	50	$	50