Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of Product Warranty Liability [Table Text Block]

The following is a summary of the change in the Company's accrued warranty reserve (in thousands):

	September 30, 2018			December 31, 2017
Warranty liability balance, beginning of the period	$	1,124		$	1,821
Product warranty accruals (reversals)	238			305
Utilization of accrual	(331		)	(1,002		)
Warranty liability balance, end of the period	$	1,031		$	1,124