3. Allowance for Doubtful Accounts

12 Months Ended

Dec. 31, 2016

Notes to Financial Statements

3. Allowance for Doubtful Accounts

Changes in the allowance for doubtful accounts are composed of the following:

	Years Ended December 31,
	2016			2015
Balance, beginning of year	$	49		$	49
Provision for doubtful accounts		17			—
Uncollectible accounts written off		(16	)		—
Balance, end of year	$	50		$	49