Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair value of assets and liabilities measured on a recurring basis

The following table presents the financial assets and liabilities the company records at fair value on a recurring basis identified by the level of inputs used to determine fair value. See Note 1 for the definitions of these levels and for further information on our financial instruments.

	December 31, 2021								December 31, 2020
$ in millions	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Financial Assets
Marketable securities	$	393	$	1	$	7	$	401	$	377	$	1	$	—	$	378
Marketable securities valued using NAV							17								18
Total marketable securities	393		1		7		418		377		1		—		396
Derivatives	—		(1)		—		(1)		—		—		—		—