Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net (loss)/earnings	$ (2,942)	$ 2,196	$ (793)	$ 4,673
Currency translation adjustments	(3)	(84)	(2)	(57)
Unrealized gain/(loss) on certain investments, net of tax of $0, $0, ($1) and $0		1	1	3
Unrealized (loss)/gain on derivative instruments [Abstract]
Unrealized (loss)/gain arising during period, net of tax of $1, ($22), $27 and ($61)	(28)	(91)	(17)	(93)
Reclassification adjustment for losses included in net earnings, net of tax of ($3), ($5), ($5) and ($24)	(1)	6	(3)	10
Total unrealized (loss)/gain on derivative instruments, net of tax	(29)	(85)	(20)	(83)
Defined benefit pension plans & other postretirement benefits [Abstract]
Amortization of prior service credits included in net periodic pension cost, net of tax of $10, $16, $30 and $47	(22)	(35)	(45)	(71)
Net actuarial gain arising during the period, net of tax of $0, $0, $0 and $0		1		1
Amortization of actuarial losses included in net periodic pension cost, net of tax of ($60), ($72), ($182) and ($217)	115	219	233	438
Settlements and curtailments included in net income, net of tax of $0, ($3), $0 and ($3)		6		6
Pension and postretirement cost related to our equity method investments, net of tax of $0, $0, $1 and $1			8	(3)
Total defined benefit pension plans and other postretirement benefits, net of tax	93	191	196	371
Other comprehensive income, net of tax	61	23	175	234
Comprehensive loss related to noncontrolling interests	(7)	(9)	(7)	(10)
Comprehensive (loss)/income, net of tax	$ (2,888)	$ 2,210	$ (625)	$ 4,897