Debt, Financing Arrangements and Leases (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Long-term debt

At December 31, 2018 and 2017, long-term debt outstanding was as follows (in thousands):

	2018			2017
Debentures:
7.08% due 2026	$	7,500		$	7,500
7.25% due 2026	200,000			200,000
Total debentures	207,500			207,500
Notes:
6.05% due 2018	—			250,000
7.85% due 2026	1,000,000			1,000,000
4.0% due 2028	400,000			—
5.4% due 2041	375,000			375,000
4.45% due 2042	400,000			400,000
4.6% due 2048	600,000			—
Total notes	2,775,000			2,025,000
Other financing obligation	1,067,286			230,926
Total long-term debt, including current portion	4,049,786			2,463,426
Unamortized debt issuance costs	(24,242		)	(15,377		)
Unamortized debt premium and discount, net	(11,137		)	(5,043		)
Long-term debt due within one year	(15,419		)	(251,430		)
Total long-term debt	$	3,998,988		$	2,191,576

Maturities of long-term debt

Aggregate minimum maturities (face value) applicable to long-term debt outstanding at December 31, 2018, for the next five years, are as follows (in thousands):

2019:     Other financing obligation	$	15,419
2020:     Other financing obligation	$	17,042
2021:     Other financing obligation	$	18,837
2022:     Other financing obligation	$	20,821
2023:     Other financing obligation	$	23,014

Future minimum lease payments

The future minimum lease payments under our various operating leases are as follows (in thousands):

2019	$	9,044
2020	9,014
2021	8,865
2022	8,808
2023	8,829
Thereafter	65,107
Total net minimum obligations	$	109,667