Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		$ 63,473	$ 63,447	$ 63,758
Other comprehensive income/(loss)		(589)	471	(130)
Distribution of Upjohn Business	[1]		(2,018)
Ending balance		77,462	63,473	63,447
Accumulated Other Comprehensive Income/(Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[2]	(5,310)	(5,367)	(5,249)
Other comprehensive income/(loss)	[2],[3]	(587)	480	(118)
Distribution of Upjohn Business	[1],[2],[4]		(423)
Ending balance	[2]	(5,897)	(5,310)	(5,367)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[2]	(5,450)	(5,936)	(6,075)
Other comprehensive income/(loss)	[2],[3]	(722)	883	139
Distribution of Upjohn Business	[2],[4]		(397)
Ending balance	[2]	(6,172)	(5,450)	(5,936)
Derivative Financial Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[2]	(428)	20	167
Other comprehensive income/(loss)	[2],[3]	547	(448)	(146)
Distribution of Upjohn Business	[2],[4]		0
Ending balance	[2]	119	(428)	20
Available-For-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[2]	116	(35)	(68)
Other comprehensive income/(loss)	[2],[3]	(336)	151	33
Distribution of Upjohn Business	[2],[4]		0
Ending balance	[2]	(220)	116	(35)
Prior Service (Costs)/Credits and Other [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[2]	452	584	728
Other comprehensive income/(loss)	[2],[3]	(75)	(106)	(144)
Distribution of Upjohn Business	[2],[4]		(26)
Ending balance	[2]	$ 377	$ 452	$ 584

[1] See Note 2B.

[2] Amounts include the impact of a change in accounting principle. See Note 1C.

[3] Amounts do not include foreign currency translation adjustments attributable to noncontrolling interests. Foreign currency translation adjustments include net losses in 2021 and net gains in 2020 and 2019 related to our equity-method investment in the Consumer Healthcare JV (see Note 2C), and the impact of our net investment hedging program.

[4] For more information, see Note 2B.