Leases (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Operating Lease, Right-of-Use Asset	$ 14,646	$ 17,069
Operating lease expense	9,200	8,600	$ 12,000
Royalty expense	127,800	$ 103,700	$ 149,500
Surety bonds outstanding	$ 26,000
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	7 years