Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair Values of Certain Financial Liabilities and Other Financial Instruments

The fair value of certain financial liabilities is shown below (in millions):  

	March 31, 2021				December 31, 2020
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Financial liabilities
Senior notes (Level 1)	$	3,066	$	3,212	$	3,065	$	3,284
Credit facility (Level 2)		2,469		2,483		2,471		2,483