Commitments and Contingencies (Tables)

3 Months Ended

Mar. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Changes in the Liability for Product Warranty Claim Costs

Changes in the liability for product warranty claim costs were as follows:

(In thousands)	Three Months Ended March 31,
	2018			2017
Balance at beginning of period	$	339		$	134
Accruals for warranties issued during the period	—			—
Settlements (in cash or in kind) during the period	(100		)	(2		)
Balance at end of period	$	239		$	132