Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Comprehensive income
Net income	$ 5,955	$ 6,960	$ 7,728
Currency translation adjustment:
Currency translation adjustment (net of tax provision (benefit) of $(134), $173 and $231)	(69)	(822)	373
Unrealized gains and losses on hedging instruments:
Reclassification adjustment for losses included in net income (net of tax benefit of $2, $1 and $17)	5	2	56
Pension and other postretirement benefit liability adjustments:
Pension and other postretirement benefit liability adjustments arising during the period (net of tax provision (benefit) of $(22), $9 and $11)	(69)	38	36
Amortization of net loss and prior service benefit included in net periodic pension cost (net of tax benefit of $1, $3 and $6)	0	5	13
Total other comprehensive income/(loss)	(133)	(777)	478
Comprehensive income	5,822	6,183	8,206
Less: comprehensive income/(loss) attributable to noncontrolling interests and redeemable noncontrolling interest	(48)	3	2
Comprehensive income attributable to Thermo Fisher Scientific Inc.	$ 5,870	$ 6,180	$ 8,204