Restructuring And Other Charges (Tables)

12 Months Ended

Dec. 31, 2020

Restructuring And Other Charges [Abstract]

Changes In Restructuring Reserve

	Restructuring
($ in millions)	Liability
Balance at December 31, 2018	$	18
Severance expense		38
Transformation costs		46
Other costs		40
Cash payments during the period		(127)
Balance at December 31, 2019		15
Severance expense		7
Transformation costs		8
Other costs		72
Cash payments during the period		(100)
Balance at December 31, 2020	$	2