Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Effective tax rate	(1.60%)	(0.40%)	(0.40%)
Tax expense attributable to the change in valuation allowance	$ 10,200
Operating loss carryforwards, state, tax effected	6,500	$ 3,700
Net change in total valuation allowance	5,600
Valuation allowance against foreign deferred tax assets	35,607	30,039
Unrecognized tax benefits	1,575	1,039	$ 651	$ 419
Recognized interest and penalties related to uncertain tax positions	3	0
Cumulative balance of interest and penalties related to uncertain tax positions	36	33
Unrecognized tax benefits, portion affecting tax rate	1,600	1,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	99,300	56,900
Federal NOL carryforwards subject to expiration	24,400
Federal NOL carryforwards not subject to expiration	74,900
Federal tax credit carryforwards	7,500	6,400
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	100,900	57,200
Swiss Federal Tax Administration (FTA) | Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	62,800	$ 56,300
Valuation allowance against foreign deferred tax assets	$ 7,300