Warranty (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Product Warranties Disclosures [Abstract]
Warranty terms, minimum	1 year
Warranty terms, maximum	4 years
Period of time following a sale the majority of claims are paid, min	6 months
Period of time following a sale the majority of claims are paid, max	9 months
Changes in warranty reserves
Beginning balance	$ 10,960	$ 10,093
Additions charged to expense	2,072	2,488
Foreign currency fluctuations	50	60
Claims paid	(2,800)	(2,766)
Ending balance	$ 10,282	$ 9,875