Commitments and Contingencies Warranty activity (Details) - Accrued Liabilities [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Product Warranty Liability [Line Items]
Standard Product Warranty Accrual	$ 853	$ 546	$ 853	$ 546	$ 717	$ 474	$ 504	$ 460
Standard Product Warranty Accrual, Warranties Issued	341	169	859	545
Standard Product Warranty Accrual, Payments	$ (205)	$ (127)	$ (480)	$ (459)