Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2020

Summary Of Carrying And Fair Values Of Long-Term Debt

The Company's long-term debt instruments, except for the revolving credit facility, are publicly-traded. A market approach, based upon quotes from financial reporting services, is used to measure the fair value of the Company's long-term debt. Because the Company's long-term debt instruments may not be actively traded, the inputs used to measure the fair value of the Company's long-term debt are classified as Level 2 inputs within the fair value hierarchy. The carrying and fair values of the Company's long-term debt are summarized in the table below.



	March 31, 2020				December 31, 2019
	Carrying Value		Fair Value		Carrying Value		Fair Value
Revolving credit facility	$	1,000	$	1,000	$	—	$	—
3.60% 2022 Senior Notes	249		244		249		255
3.60% 2026 Senior Notes	743		687		742		777
Loan related to tax-exempt waste disposal revenue bonds due 2027	11		11		11		11
6 ½% 2029 GO Zone Senior Notes	99		98		99		103
6 ½% 2035 GO Zone Senior Notes	88		92		88		92
6 ½% 2035 IKE Zone Senior Notes	65		65		65		68
5.0% 2046 Senior Notes	677		651		677		761
4.375% 2047 Senior Notes	491		395		491		505
3.50% 2032 GO Zone Refunding Senior Notes	249		239		249		267
1.625% 2029 Senior Notes	760		688		774		785