Debt and Financing Arrangements (Tables)

12 Months Ended

Dec. 31, 2020

Debt Disclosure [Abstract]

Long-term debt

At December 31, 2020 and 2019, long-term debt outstanding was as follows (in thousands): 

	2020		2019
Debentures:
7.08% due 2026	$	7,500	$	7,500
7.25% due 2026	200,000		200,000
Total debentures	207,500		207,500
Notes:
7.85% due 2026	1,000,000		1,000,000
4.0% due 2028	400,000		400,000
3.25% due 2030	700,000		—
5.4% due 2041	375,000		375,000
4.45% due 2042	400,000		400,000
4.6% due 2048	600,000		600,000
3.95% due 2050	500,000		—
Total notes	3,975,000		2,775,000
Other financing obligations	1,104,143		1,115,980
Total long-term debt, including current portion	5,286,643		4,098,480
Unamortized debt issuance costs	(32,505)		(22,876)
Unamortized debt premium and discount, net	(14,358)		(10,634)
Long-term debt due within one year	(22,640)		(20,180)
Total long-term debt	$	5,217,140	$	4,044,790

Maturities of long-term debt

Aggregate minimum maturities (face value) applicable to long-term debt outstanding at December 31, 2020, for the next five years, are as follows (in thousands): 

2021:     Other financing obligations	$	22,640
2022:     Other financing obligations	$	24,762
2023:     Other financing obligations	$	27,082
2024:     Other financing obligations	$	29,621
2025:     Other financing obligations	$	32,397

Future minimum lease payments

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