Acquisition Pro Forma Results (Details) - PPD, Inc. [Member] - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition, Pro Forma Information [Abstract]
Revenues		$ 44,886	$ 36,887
Net income attributable to Thermo Fisher Scientific Inc.		7,369	5,361
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	$ 378
Business Combination, Pro Forma Information, Operating Income (Loss) of Acquiree since Acquisition Date, Actual	$ (60)
Non-recurring Pro Forma Adjustments, Transaction Costs [Member]
Business Acquisition, Pro Forma Information [Abstract]
Net income attributable to Thermo Fisher Scientific Inc.		$ 312	$ (197)

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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