Accounts Receivable and Sales Concentrations

12 Months Ended

Dec. 31, 2019

Receivables [Abstract]

Accounts Receivable and Sales Concentrations

Accounts receivable, net are comprised of the following amounts:

	As of December 31,
	2019		2018
Trade	$	132,910	$	135,260
Less—allowance for doubtful accounts	1,352		1,839
Accounts receivable, net	$	131,558	$	133,421

The following table presents changes in allowance for doubtful accounts.

	Year Ended December 31,
	2019			2018			2017
Balance at beginning of year	$	1,839		$	1,719		$	1,069
Additions	449			754			648
Write-offs	(924		)	(584		)	(101		)
Currency impact	(12		)	(50		)	103
Balance at end of year	$	1,352		$	1,839		$	1,719