Product Warranties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2014	Jun. 30, 2013
Product Warranties Disclosures [Abstract]
Maximum product warranty term				3 years
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of period	$ 3,244	$ 2,743	$ 4,455	$ 2,965	$ 4,455
Charges to operations	412	372		826	490
Deductions for costs incurred	(175)	(145)		(350)	(1,166)
Changes in estimates	(118)	(287)	(800)	(78)	(1,096)
Balance, end of period	$ 3,363	$ 2,683	$ 2,743	$ 3,363	$ 2,683