Restructuring Charges (Narrative) (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 1,171	$ 1,171
Outstanding restructuring liabilities	586	586
One-time Employee Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	732	732
Lease Modification Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	326	326
Losses On Disposal Of Assets [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 113	$ 113