Annual report pursuant to Section 13 and 15(d)

Income Taxes (Narrative) (Details)

v3.20.1
Income Taxes (Narrative) (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Income Tax Disclosure [Line Items]      
Statutory income tax (benefit) expense 21.00% 21.00% (34.00%)
Net change in valuation allowance $ (13,490) $ (3,689) $ (21,851)
Tax Cuts and Jobs Act of 2017, Percentage of Deferred Tax Asset Which Can be Used for Offset 80.00%    
Net operating loss carryforwards for U.S. federal income tax purposes $ 131,621    
Research and experimentation credit carryforwards 4,250    
Unrecognized tax benefits that would impact effective tax rate 561 545  
Unrecognized tax benefits that reduce deferred tax assets 462 384  
Interest and penalty expense recognized 0 0 $ 13
Total accrued interest and penalties $ 4 $ 9  
Minimum [Member]      
Income Tax Disclosure [Line Items]      
Foreign statutory tax rate, foreign operations 25.00%