Product Warranty (Tables)

6 Months Ended

Jun. 30, 2015

Product Warranties Disclosures [Abstract]

Summary of product warranty activity

The following table summarizes product warranty activity during 2015 and 2014:

	Six Months Ended
	June 30,
	2015			2014
Beginning balance	$	1,853		$	1,269
Charges to expense	538			967
Costs incurred	(632		)	(620		)
Ending balance	$	1,759		$	1,616