Property, Plant and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, Plant and Equipment:

Property, plant and equipment, at cost, consist of the following at December 31, 2023 and 2022 (in thousands):

	Useful Lives (Years)	December 31,
		2023		2022
Land	—	$	297,435	$	172,464
Land improvements	10 – 30	316,544		201,284
Buildings and improvements	10 – 50	699,045		492,509
Machinery and equipment(a)	2 – 45	6,173,463		4,446,315
Mineral rights and reserves	7 – 60	1,689,013		1,795,668
Construction in progress	—	3,058,257		2,246,090
Total		$	12,233,757	$	9,354,330

(a)Consists primarily of (1) short-lived production equipment components, office and building equipment and other equipment with estimated lives ranging 2 – 7 years, (2) production process equipment (intermediate components) with estimated lives ranging 8 – 19 years, (3) production process equipment (major unit components) with estimated lives ranging 20 – 29 years, and (4) production process equipment (infrastructure and other) with estimated lives ranging 30 – 45 years.

The cost of property, plant and equipment is depreciated generally by the straight-line method. Depletion of mineral rights is based on the units-of-production method. Depreciation expense, including depletion, amounted to $398.5 million, $273.0 million and $225.6 million during the years ended December 31, 2023, 2022 and 2021, respectively. Interest capitalized on significant capital projects in 2023, 2022 and 2021 was $72.7 million, $31.1 million and $50.0 million, respectively.

In October 2022, the Company announced it has been awarded a nearly $150 million grant from the U.S. Department of Energy to expand domestic manufacturing of batteries for EVs and the electric grid and for materials and components currently imported from other countries. The grant funding is intended to support a portion of the anticipated cost to construct a new, commercial-scale U.S.-based lithium concentrator facility at our Kings Mountain, North Carolina location. The grant will be received over the life of the construction period for the new facility (projected as 2024 to 2026) as reimbursement for capital expenditures. To further support the restart of the Kings Mountain mine, in August 2023, we announced a $90 million critical materials award from the U.S. Department of Defense. As funds are received for both of these grants, the Company will reduce the cost of the assets by the amount of the grant, and income will be recognized by the lower depreciation expense over the useful life of the assets.