Summary of Significant Accounting Policies Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) months revenue_sources	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Product Liability Contingency [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	$ 58	$ 100
Amortization of intangible assets	1,658	1,707	$ 1,740
Provision for inventory reserves and purchase order commitments	$ 0	0	306
New Product Warranty Period	12 months
Refurbished Product Warranty Period	3 months
Cash and Cash Equivalents [Abstract]
Cash Equivalents, Original Maturity Date of Acquisition, Maximum (in months) | months	3
Property, Plant and Equipment [Abstract]
Depreciation, Depletion and Amortization	$ 5,400	6,500	$ 6,400
Revenue Recognition [Abstract]
Number of Revenue Sources from Products and Services | revenue_sources	4
Deferred Revenue [Abstract]
Deferred Revenue, Current	$ 4,600	5,300
Deferred Costs, Current	$ 200	$ 800
Minimum [Member] | Equipment [Member]
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Useful Life, Minimum (in years)	3 years
Maximum [Member] | Equipment [Member]
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Useful Life, Minimum (in years)	9 years