Summary of Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) country	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Accounting Policies [Line Items]
Number of countries in which entity operates | country	50
Allowance for Doubtful Accounts Activity [Roll Forward]
Balance, beginning of period	$ 2,990	$ 2,969	$ 2,718
Expense (reversal)	319	402	473
Write-offs	(293)	(85)	(263)
Translation adjustments	(227)	(296)	41
Balance, end of period	$ 2,789	2,990	2,969
Post-production service lIfe	8 years
Valuation Allowances and Reserves Charged to Cost and Expense, Manufacturing Inventory	$ 5,900	6,300	4,800
Valuation Allowances and Reserves Charged to Cost and Expense, Spare Parts Inventory	9,800	10,000	8,600
Impairment of Intangible Assets, Finite-lived	$ 8,400	900
Revenue recognition, installation deferral percentage	4.00%
Research and development subsidies	$ (3,300)	(4,500)	(5,300)
Advertising expense	$ 3,100	$ 3,400	$ 4,100
Stock options, vesting period	4 years
Stock options, average legal life	7 years
Building and Building Improvements [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	40 years
Machinery and Equipment [Member] | Minimum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	3 years
Machinery and Equipment [Member] | Maximum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	7 years
Demonstration Systems [Member] | Minimum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	3 years
Demonstration Systems [Member] | Maximum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	7 years
Other Fixed Assets [Member] | Minimum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	3 years
Other Fixed Assets [Member] | Maximum [Member]
Allowance for Doubtful Accounts Activity [Roll Forward]
Property, plant and equipment, estimated useful life	7 years