Accumulated Other Comprehensive Loss - Schedule of AOCI Components (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Components of accumulated other comprehensive loss
Beginning balance		$ 14,309	$ 12,911	$ 15,358	$ 13,687
Beginning balance, tax effect					1,492
Changes in value (net of tax effect)				2	7
Changes in value, tax effect				4	2
Reclassifications into earnings (net of tax effect)				50	124
Reclassifications into earnings, tax effect				123	38
Ending balance	$ 8,690	8,690	13,958	8,690	13,958
Ending balance, tax effect			1,452		1,452
Tax benefit		1,297	(464)	1,370	(680)
Accumulated Other Comprehensive Income
Components of accumulated other comprehensive loss
Beginning balance		(7,898)	(7,766)	(7,989)	(7,825)
Beginning balance, tax effect				1,549
Ending balance	(7,937)	(7,937)	(7,694)	(7,937)	(7,694)
Ending balance, tax effect	1,431	1,431		1,431
Pension and Other Benefit Liabilities
Components of accumulated other comprehensive loss
Beginning balance				(8,095)	(7,925)
Changes in value (net of tax effect)				(6)	6
Reclassifications into earnings (net of tax effect)				133	124
Ending balance	(7,968)	(7,968)	(7,795)	(7,968)	(7,795)
Deferred income taxes related to pension obligation				755
Other
Components of accumulated other comprehensive loss
Beginning balance				106	100
Changes in value (net of tax effect)				8	1
Reclassifications into earnings (net of tax effect)				(83)	0
Ending balance	31	$ 31	$ 101	$ 31	$ 101
Foreign currency hedges | Released from AOCI
Components of accumulated other comprehensive loss
Tax benefit	$ 83