Warranties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Change in the Company's warranty reserve
Liability, beginning of period	$ 1,498	$ 1,220	$ 1,385	$ 1,374
Provision for warranties issued during the year, net of adjustments	307	567	596	877
Adjustments to warranties issued during previous years	14	(43)	(23)	(396)
Warranty claims	(165)	(225)	(304)	(336)
Liability, end of period	$ 1,654	$ 1,519	$ 1,654	$ 1,519