Long-Term Debt

9 Months Ended

Sep. 30, 2025

Our outstanding long-term debt is shown below:


	September 30,		December 31,
(in millions)	2025		2024
Uncollateralized Senior Notes:
5.68% notes, due June 2026	$	2.9	$	5.8
6.39% notes, due December 2026	100.0		100.0
6.44% notes, due December 2027	100.0		100.0
6.43% notes, due May 2028	2.1		2.8
4.88% notes, due August 2028	60.0		—
3.73% notes, due December 2028	8.0		8.0
6.45% notes, due December 2028	100.0		100.0
3.88% notes, due May 2029	20.0		25.0
5.20% notes, due November 2029	100.0		100.0
5.02% notes, due September 2030	50.0		—
6.62% notes, due December 2030	100.0		100.0
5.16% notes, due August 2031	90.0		—
3.25% notes, due April 2032	47.3		52.5
6.71% notes, due December 2033	100.0		100.0
2.98% notes, due December 2034	70.0		70.0
3.00% notes, due July 2035	50.0		50.0
2.96% notes, due August 2035	40.0		40.0
2.49% notes, due January 2037	50.0		50.0
5.43% notes, due March 2038	80.0		80.0
3.48% notes, due May 2038	50.0		50.0
3.58% notes, due November 2038	50.0		50.0
6.73% notes, due December 2038	50.0		50.0
3.98% notes, due August 2039	100.0		100.0
2.95% notes, due March 2042	50.0		50.0
Equipment security note
2.46% note, due September 2031	6.0		6.7
Less: debt issuance costs	(3.9)		(3.6)
Total long-term debt	1,472.4		1,287.2
Less: current maturities	(34.5)		(25.5)
Total long-term debt, net of current maturities	$	1,437.9	$	1,261.7

Terms of the Senior Notes

All of our outstanding Senior Notes set forth certain business covenants to which we are subject when any note is outstanding, including covenants that limit or restrict our ability, and the ability of our subsidiaries, to incur indebtedness, or place or permit liens and encumbrances on any of our property or the property of our subsidiaries.

Senior Notes

In August 2025, we entered into a Note Purchase Agreement for the issuance of Senior Notes in the aggregate principal amount of $200.0 million with an initial funding of $150.0 million in August 2025 and an additional $50.0 million in September 2025. These Senior Notes have an average interest rate of 5.04 percent consisting of $60.0 million of 4.88 percent notes due in August 2028, $50.0 million of 5.02 percent notes due in September 2030, and $90.0 million of 5.16 percent notes due in August 2031. The proceeds received were used to reduce short-term borrowings under our Revolver and to fund capital expenditures. The outstanding principal balance of the Senior Notes will be due on their respective maturity dates with interest payments payable semiannually beginning in 2026

until the principal has been paid in full. These Senior Notes have similar covenants and default provisions as our other Senior Notes.

On November 1, 2024, we issued 5.20 percent Senior Notes due in November 2029 in the aggregate principal amount of $100.0 million. The proceeds received were used to reduce short-term borrowings under our Revolver and to fund capital expenditures. These Senior Notes have similar covenants and default provisions as our other Senior Notes, and have semi-annual interest payments due on May 1 and November 1 of each year which began in 2025.

Shelf Agreements

We have entered into Shelf Agreements with Prudential and MetLife with terms that extend through February 2026 and June 2030, respectively, however neither of such lenders have any obligation to purchase debt thereunder. In June 2025, we amended our Shelf Agreement with MetLife to expand the total borrowing capacity and extend the term of the agreement for an additional five years. At September 30, 2025, a total of $305.0 million of borrowing capacity was available under these Shelf Agreements.