Product Warranty (Tables)

3 Months Ended

Mar. 31, 2017

Product Warranties Disclosures [Abstract]

Summary of product warranty activity

The following table summarizes product warranty activity during 2017 and 2016:

	Three Months Ended
	March 31,
	2017			2016
Beginning balance	$	2,280		$	1,880
Charges to expense	237			528
Costs incurred	(122		)	(333		)
Ending balance	$	2,395		$	2,075