Fair Value of Financial Instruments (Unaudited) (Tables)

9 Months Ended

Sep. 30, 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:

	September 30, 2021						December 31, 2020
$ in millions	Level 1		Level 2		Total		Level 1		Level 2		Total
Financial Assets
Marketable securities	$	390	$	—	$	390	$	377	$	1	$	378
Marketable securities valued using NAV					16						18
Total marketable securities	390		—		406		377		1		396
Derivatives	—		3		3		—		—		—