Income Taxes - Change In Valuation Allowance (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
A reconciliation of the current year change in valuation allowance
Increase (decrease) in valuation allowance for current year increase in net operating losses	$ 7,450
Increase in valuation allowance for current year net increase in deferred tax assets other than net operating losses	14,878
Decrease in valuation allowance as a result of foreign currency fluctuation	(1,534)
Increase in valuation allowance due to acquisition of Hypulsion	3,789
Net increase in Valuation allowance	24,583
U.S.
A reconciliation of the current year change in valuation allowance
Increase (decrease) in valuation allowance for current year increase in net operating losses	8,345
Increase in valuation allowance for current year net increase in deferred tax assets other than net operating losses	14,237
Net increase in Valuation allowance	22,582
Foreign
A reconciliation of the current year change in valuation allowance
Increase (decrease) in valuation allowance for current year increase in net operating losses	(895)
Increase in valuation allowance for current year net increase in deferred tax assets other than net operating losses	641
Decrease in valuation allowance as a result of foreign currency fluctuation	(1,534)
Increase in valuation allowance due to acquisition of Hypulsion	3,789
Net increase in Valuation allowance	$ 2,001