Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2017

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 warranty accrual reserve (in thousands):

	Six Months Ended
	June 30,
	2017			2016
Warranty liability balance, beginning of the period	$	1,821		$	2,553
Product warranty accruals	445			754
Utilization of accrual	(672		)	(1,146		)
Warranty liability balance, end of the period	$	1,594		$	2,161