Warranties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Change in the Company's warranty reserve
Liability, beginning of year	$ 953	$ 1,385	$ 1,374
Provision for warranties issued during the year, net of adjustments	1,235	1,263	1,453
Provision for warranties issued in previous years, net of adjustments	(16)	(261)	(788)
Warranty claims	(757)	(1,434)	(654)
Liability, end of year	$ 1,415	$ 953	$ 1,385