Restructuring Costs (Tables)

6 Months Ended

Jun. 30, 2019

Restructuring And Related Activities [Abstract]

Summary of Restructuring Costs

The types of charges for restructuring costs for the three and six months ended June 30, 2019 and June 30, 2018 were (in thousands):  

	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Severance and benefits	$	1,001	$	-	$	-	$	-
Asset impairment charge (see Note 11)		375		-		-		-
Total	$	1,376	$	-	$	-	$	-

Summary of Activity and Estimated Timing of Future Payouts for Accrued Restructuring Costs

  The following tables show the activity and estimated timing of future payouts for accrued restructuring costs (in thousand):

	Three Months Ended June 30,
	2019			2018
Balance as of March 31, 2019	$	-		$	-
Restructuring costs		1,376			-
Adjustments of prior estimates		-			-
Non-cash asset impairment charge		(375	)		-
Cash payments		(340	)		-
Balance as of June 30, 2019	$	661		$	-
	Six Months Ended June 30,
	2019			2018
Balance as of December 31, 2018	$	-		$	-
Restructuring costs		1,376			-
Adjustments of prior estimates		-			-
Non-cash asset impairment charge		(375	)		-
Cash payments		(340	)		-
Balance as of June 30, 2019	$	661		$	-
	As of June 30,
Estimated timing of future payments:	2019			2018
Remainder of 2019	$	573		$	-
2020		88			-
Total stock-based compensation expense	$	661		$	-