Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Oct. 30, 2022	Dec. 31, 2019	Oct. 30, 2019	Dec. 29, 2016
Lessee, Lease, Description [Line Items]
Term of lease contract								10 years
Renewal term of lease contract								5 years
Cash collateral as security	$ 606		$ 606			$ 909
Lease expense	700	$ 700	1,400	$ 1,400
Right of use asset amortization	$ 400	$ 300	$ 700	$ 600
Standby Letters of Credit
Lessee, Lease, Description [Line Items]
Security deposit							$ 600	$ 900
Forecast | Standby Letters of Credit
Lessee, Lease, Description [Line Items]
Security deposit					$ 300