Non-Mineral Leases (Lease Term and Discount Rate) (Details)	Dec. 31, 2021	Dec. 31, 2020
Non-Mineral Leases [Abstract]
Weighted-average term (years): Operating leases	5 years 11 months 19 days	6 years 1 month 9 days
Weighted-average term (years): Finance leases	7 years 5 months 26 days	7 years 1 month 13 days
Weighted-average discount rate (percent): Operating leases	2.66%	2.78%
Weighted-average discount rate (percent): Finance leases	3.24%	4.27%