Goodwill (Tables)

9 Months Ended

Sep. 30, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

Changes in the carrying amount of goodwill by reportable segment are as follows:

(Dollars in millions)	AST		NC&C		IMS		Total
Balance as of December 31, 2020	$	363	$	275	$	419	$	1,057
Acquisitions	14		—		—		14
Balance as of September 30, 2021	377		275		419		1,071