Leases (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2017
Lessee, Lease, Description [Line Items]
Total equity		$ (608,280)	$ (819,865)	$ (702,689)	$ (573,015)
Term of lease contract			1 year
Lease expense		8,400
Payments to acquire buildings	$ 5,800
Right-of-use assets included in Property, plant and equipment, net			$ 8,976	15,689
Cumulative Effect, Period of Adoption, Adjustment
Lessee, Lease, Description [Line Items]
Total equity		(35)		1,443	$ 5,395
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings, Pre-Tax
Lessee, Lease, Description [Line Items]
Total equity		$ 300		$ 300
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term			1 year
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term			9 years
Renewal lease term			10 years