CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) (UNAUDITED) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2024	Jul. 02, 2023	Jun. 30, 2024	Jul. 02, 2023
Statement of Comprehensive Income [Abstract]
Net income before allocation to noncontrolling interests		$ 48	$ 2,338	$ 3,171	$ 7,894
Foreign currency translation adjustments, net		(70)	242	70	343
Unrealized holding gains/(losses) on derivative financial instruments, net		127	109	343	112
Reclassification adjustments for (gains)/losses included in net income	[1]	(147)	(163)	(159)	140
Other comprehensive income, cash flow hedge, gain (loss), before tax, total		(21)	(54)	184	251
Unrealized holding gains/(losses) on available-for-sale securities, net		(25)	26	(77)	113
Reclassification adjustments for (gains)/losses included in net income/(loss)	[2]	100	16	86	(493)
Other comprehensive income (loss), available-for-sale securities, before tax, total		74	42	9	(379)
Reclassification adjustments related to amortization of prior service costs and other, net		(28)	(30)	(56)	(59)
Reclassification adjustments related to curtailments of prior service costs and other, net		0	(7)	0	(12)
Defined benefit plan, amounts recognized in other comprehensive income (loss), net prior service costs and other, before tax		(28)	(37)	(56)	(72)
Other comprehensive income/(loss), before tax		(44)	193	207	143
Tax provision/(benefit) on other comprehensive income/(loss)		22	9	76	(53)
Other comprehensive income/(loss) before allocation to noncontrolling interests		(67)	184	131	196
Comprehensive income/(loss) before allocation to noncontrolling interests		(19)	2,522	3,302	8,091
Less: Comprehensive income/(loss) attributable to noncontrolling interests		(2)	8	1	18
Comprehensive income/(loss) attributable to Pfizer Inc.		$ (17)	$ 2,514	$ 3,302	$ 8,072

[1] Reclassified into Other (income)/deductions—net and Cost of sales. See Note 7E.

[2] Reclassified into Other (income)/deductions—net.