DEBT (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Debt

Debt is detailed as follows:

in millions	Effective Interest Rates	March 31 2024		December 31 2023		March 31 2023
Bank line of credit expires 2027 1		$	0.0	$	0.0	$	0.0
Commercial paper expires 2027 1		0.0		0.0		0.0
Total short-term debt		$	0.0	$	0.0	$	0.0
Bank line of credit expires 2027 1		$	0.0	$	0.0	$	0.0
Commercial paper expires 2027 1		550.0		550.0		550.0
4.50% notes due 2025	4.65%	400.0		400.0		400.0
5.80% notes due 2026		0.0		550.0		550.0
3.90% notes due 2027	4.00%	400.0		400.0		400.0
3.50% notes due 2030	3.94%	750.0		750.0		750.0
7.15% notes due 2037	8.05%	129.2		129.2		129.2
4.50% notes due 2047	4.59%	700.0		700.0		700.0
4.70% notes due 2048	5.42%	460.9		460.9		460.9
Other notes	0.47%	1.0		1.4		1.5
Total long-term debt - face value		$	3,391.1	$	3,941.5	$	3,941.6
Unamortized discounts and debt issuance costs		(59.9)		(63.4)		(67.2)
Fair value adjustments 2		0.0		(0.3)		3.0
Total long-term debt - book value		$	3,331.2	$	3,877.8	$	3,877.4
Less current maturities		(0.5)		(0.5)		(0.5)
Total long-term debt - reported value		$	3,330.7	$	3,877.3	$	3,876.9
Estimated fair value of long-term debt		$	3,205.2	$	3,798.0	$	3,770.2

1Borrowings on the bank line of credit and commercial paper are classified as short-term if we intend to repay within twelve months and as long-term if we have the intent and ability to extend payment beyond twelve months.

2See Note 6 for additional information on our fair value hedging strategy.

Standby Letters of Credit

Our standby letters of credit as of March 31, 2024 are summarized by purpose in the table below:

in millions
Risk management insurance	$	80.5
Reclamation/restoration requirements	8.7
Total	$	89.2