Income Taxes (Significant Valuation Allowances) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Tax Credit Carryforward [Line Items]
Valuation allowance	$ 14,867	$ 14,455
United States
Tax Credit Carryforward [Line Items]
Valuation allowance	11,800	12,300
Domestic Tax Authority | United States
Tax Credit Carryforward [Line Items]
Valuation allowance	3,395	4,240
State and Local Jurisdiction
Tax Credit Carryforward [Line Items]
Valuation allowance	800	1,000
State and Local Jurisdiction | United States
Tax Credit Carryforward [Line Items]
Valuation allowance	8,411	8,057
Capital Loss Carryforward | Israel
Tax Credit Carryforward [Line Items]
Valuation allowance	$ 2,457	$ 1,457