Annual report pursuant to Section 13 and 15(d)

Income Taxes - Narrative (Details)

v3.19.1
Income Taxes - Narrative (Details) - USD ($)
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Income Taxes [Line Items]    
Increase in the valuation allowance $ (5,600,000)  
Uncertain tax positions interest and penalties accrued 0 $ 0
Effect of remeasurement of deferred tax assets and liabilities under Tax Cuts and Jobs Act   $ 3,700,000
Federal    
Income Taxes [Line Items]    
Net operating loss carryforwards 15,300,000  
State    
Income Taxes [Line Items]    
Net operating loss carryforwards 20,100,000  
Germany | Corporate Income Tax Carryforwards    
Income Taxes [Line Items]    
Net operating loss carryforwards 80,300,000  
Germany | Trade Tax Carryforwards    
Income Taxes [Line Items]    
Net operating loss carryforwards $ 79,400,000