Restructuring Costs (Tables)

9 Months Ended

Sep. 30, 2018

Restructuring and Related Activities [Abstract]

Summary of Restructuring Activities

The following table summarizes restructuring activities for the three months ended September 30, 2018 and 2017:

	Three Months Ended September 30,
	2018			2017
	(in thousands)
Beginning balance	$	86		$	206
Adjustments to research and development expense		(10	)		(38	)
Cash payments		(5	)		(58	)
Ending balance	$	71		$	110

The following table summarizes restructuring activities for the nine months ended September 30, 2018 and 2017:

	Nine Months Ended September 30,
	2018			2017
	(in thousands)
Beginning balance	$	137		$	763
Adjustments to research and development expense		(10	)		(112	)
Cash payments		(56	)		(541	)
Ending balance	$	71		$	110