Leases (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Jun. 29, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Payment of purchase option to acquire property	$ 5,000
Finance lease obligation	380		$ 5,077
Finance lease right-of-use assets	418		7,017
Germany
Lessee, Lease, Description [Line Items]
Finance lease obligation		$ 4,200	4,500
Finance lease right-of-use assets		$ 6,100	$ 6,500
Finance lease right-of-use asset, accumulated amortization	$ 4,500