Warranty (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 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	8,879	8,888
Acquired warranty obligations	384	0
Foreign currency fluctuations	225	85
Claims paid	(8,912)	(8,707)
Ending balance	$ 11,536	$ 10,359