Long-Term Debt (Tables)

9 Months Ended

Sep. 30, 2023

Debt Disclosure [Abstract]

Outstanding Long-Term Debt

Our outstanding long-term debt is shown below: 

	September 30,		December 31,
(in thousands)	2023		2022
Uncollateralized senior notes:
5.93% note, due October 31, 2023	$	1,500	$	3,000
5.68% note, due June 30, 2026	8,700		11,600
6.43% note, due May 2, 2028	3,500		4,200
3.73% note, due December 16, 2028	12,000		12,000
3.88% note, due May 15, 2029	30,000		35,000
3.25% note, due April 30, 2032	61,250		66,500
3.48% note, due May 31, 2038	50,000		50,000
3.58% note, due November 30, 2038	50,000		50,000
3.98% note, due August 20, 2039	100,000		100,000
2.98% note, due December 20, 2034	70,000		70,000
3.00% note, due July 15, 2035	50,000		50,000
2.96% note, due August 15, 2035	40,000		40,000
2.49% notes Due January 25, 2037	50,000		50,000
2.95% notes Due March 15, 2042	50,000		50,000
5.43% notes Due March 14, 2038	80,000		—
Equipment security note
2.46% note, due September 24, 2031	7,856		8,517
Less: debt issuance costs	(1,005)		(946)
Total long-term debt	663,801		599,871
Less: current maturities	(20,000)		(21,483)
Total long-term debt, net of current maturities	$	643,801	$	578,388

Schedule of Line of Credit Facilities [Line Items]

Schedule of Line of Credit Facilities [Table Text Block]

(in thousands)	Total Borrowing Capacity		Less: Amount of Debt Issued		Less: Unfunded Commitments		Remaining Borrowing Capacity
Shelf Agreements (1)
Prudential Shelf Agreement	$	405,000	$	(300,000)	$	—	$	105,000
MetLife Shelf Agreement	200,000		(50,000)		—		150,000
Total Shelf Agreements as of September 30, 2023	$	605,000	$	(350,000)	$	—	$	255,000