Property, Plant and Equipment (Details) - USD ($) $ in Thousands		Dec. 31, 2023	Dec. 31, 2022
Property, plant and equipment
Operational Mining Properties Gross		$ 1,358,189	$ 1,533,385
Mineral Interest		809,912	821,112
Land		8,318	8,242
Buildings and Improvements, Gross	[1]	947,435	800,957
Property, Plant and Equipment, Gross		3,736,719	3,399,715
Accumulated depreciation and amortization	[2]	(2,048,431)	(2,009,960)
Construction in Progress, Gross	[3]	612,865	236,019
Property, plant and equipment and mining properties, net		$ 1,688,288	$ 1,389,755

[1] Includes $127.6 million and $148.2 million associated with facilities and equipment assets under finance leases at December 31, 2023 and December 31, 2022, respectively.

[2] Includes $37.6 million and $80.3 million of accumulated amortization related to assets under finance leases at December 31, 2023 and December 31, 2022, respectively.

[3] Includes $471.7 million and $139.7 million of construction costs related to the Rochester Expansion project at December 31, 2023 and December 31, 2022, respectively.