Long-term Debt and Interest Expense (Tables)

12 Months Ended

Dec. 31, 2019

Debt Disclosure [Abstract]

Components of long-term debt

The components of long-term debt, including the effects of issuance costs and issuance discounts, are as follows:

	As of December 31,
	2019		2018
	(in millions)
Outstanding debt principal balances:
7.50% senior notes due 2020	$	450	$	450
3.45% senior notes due 2021	500		500
3.95% senior notes due 2022	600		600
4.45% senior notes due 2026	500		500
7.20% senior notes due 2028	250		250
	2,300		2,300
Issuance costs and discounts	(11)		(16)
Total debt	2,289		2,284
Less current portion of long-term debt	450		—
Long-term debt	$	1,839	$	2,284

Principal maturities of long-term debt

Principal payments scheduled to be made on the Company's long-term debt are as follows (in millions):

2020	$	450
2021	$	500
2022	$	600
2023	$	—
2024	$	—
Thereafter	$	750

Interest expense

Interest expense activity is as follows:

	Year Ended December 31,
	2019		2018		2017
	(in millions)
Cash payments for interest	$	117	$	133	$	164
Accretion of finance lease	4		—		—
Amortization of issuance discounts	1		1		1
Amortization of capitalized loan fees	4		4		4
Net changes in accruals	—		(6)		(9)
Interest incurred	126		132		160
Less capitalized interest	(5)		(6)		(7)
Total interest expense	$	121	$	126	$	153