Financial Instruments and Other Guarantees (Tables)

3 Months Ended

Mar. 31, 2026

Guarantees and Product Warranties [Abstract]

Financial Instruments and Guarantees with Off Balance Sheet Risk

The following table summarizes the Company’s financial instruments that carry off-balance-sheet risk.


	March 31, 2026
	Reclamation Support		Other Support (1)		Total
	(Dollars in millions)
Surety bonds	$	937.5	$	82.1	$	1,019.6
Letters of credit (2)	53.5		61.7		115.2
	991.0		143.8		1,134.8
Less: Letters of credit in support of surety bonds (3)	(53.5)		(1.7)		(55.2)
Obligations supported, net	$	937.5	$	142.1	$	1,079.6

(1) Instruments support obligations related to leases, health care plans, workers’ compensation, property and casualty insurance, customer and vendor contracts and certain restoration ancillary to prior mining activities.

(2) Amounts do not include cash-collateralized letters of credit.

(3) Certain letters of credit serve as collateral for surety bonds at the request of surety bond providers.

Restricted Cash and Collateral

Portions of the restricted cash balances and deposits are held in accounts denominated in Australian dollars.


	March 31, 2026		December 31, 2025
	(Dollars in millions)
Restricted cash (1)
Surety trust accounts (2)	$	377.7	$	383.6
Credit support facilities (2) (3)	298.2		325.6
	675.9		709.2
Other cash collateral (1)
Deposits with regulatory authorities for reclamation and other obligations (3)	135.4		134.9


Restricted cash and collateral	$	811.3	$	844.1

(1) Restricted cash balances are combined with unrestricted cash and cash equivalents in the accompanying unaudited condensed consolidated statements of cash flows; changes between unrestricted cash and cash equivalents and restricted cash balances are thus not reflected in the operating, investing or financing activities therein. Changes in other cash collateral balances are reflected as operating activities therein.

(2) Surety trust accounts, the funding for collateralized letters of credit and cash supporting the bank guarantee facilities are comprised of highly liquid investments with original maturities of three months or less; interest and other earnings on such funds accrue to the Company.

(3) At March 31, 2026, the Australian dollar denominated balances supporting the bank guarantee facilities and the deposits with regulatory authorities were $319 million and $198 million, respectively. At December 31, 2025, the Australian dollar denominated balances supporting the bank guarantee facilities and the deposits with regulatory authorities were $312 million and $201 million, respectively.