Warranty (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 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	5,815	5,946
Acquired warranty obligations	384	0
Foreign currency fluctuations	154	48
Claims paid	(5,872)	(5,766)
Ending balance	$ 11,441	$ 10,321