Leases (Narrative) (Details) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($) lease
Lessee, Lease, Description [Line Items]
Operating lease right of use assets (Note 9)	$ 307		$ 614
Operating Lease, Liability	5,961		$ 12,900
Number of leases abandoned | lease			14
Restricted cash in prepaid expenses and other current assets	1,274	$ 0
Gain on settlement of leases	$ 3,322	$ 0
Minimum
Leases [Abstract]
Operating leases remaining lease term	1 year
Lessee, Lease, Description [Line Items]
Operating leases remaining lease term	1 year
Maximum
Leases [Abstract]
Operating leases remaining lease term	5 years
Lessee, Lease, Description [Line Items]
Operating leases remaining lease term	5 years