Fair Value of Financial Instruments (Unaudited) (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair value information of assets and liabilities measured at fair value 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:

	March 31, 2021						December 31, 2020
$ in millions	Level 1		Level 2		Total		Level 1		Level 2		Total
Financial Assets (Liabilities)
Marketable securities	$	397	$	1	$	398	$	377	$	1	$	378
Marketable securities valued using NAV					17						18
Total marketable securities	397		1		415		377		1		396
Derivatives	—		(1)		(1)		—		—		—