Commitments and Contingencies - Narratives (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Class of Warrant or Right [Line Items]
Purchase Commitment, remaining minimum amount committed	$ 300	$ 2,200
Accrued warranty reserve	1,466	2,036
Accrued warranty reserve	$ 355	$ 517
Minimum
Class of Warrant or Right [Line Items]
Warranty, Term	12 months
Maximum
Class of Warrant or Right [Line Items]
Warranty, Term	24 months