Contract Assets and Liabilities (Tables)

3 Months Ended

Mar. 31, 2021

Revenue from Contract with Customer [Abstract]

Contract with Customer, Asset and Liability [Table Text Block]

Total contract assets and contract liabilities as of March 31, 2021 and December 31, 2020 are as follows:

(dollars in millions)	March 31, 2021		December 31, 2020
Contract assets	$	10,238	$	9,931
Contract liabilities	(12,879)		(12,889)
Net contract liabilities	$	(2,641)	$	(2,958)