v3.26.3
Supplemental Income Statement Information - Schedule of Earnings Per Share (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
3 Months Ended 9 Months Ended
Sep. 26, 2026
Sep. 27, 2025
Sep. 26, 2026
Sep. 27, 2025
Supplemental Income Statement Elements [Abstract]        
Net income attributable to Thermo Fisher Scientific Inc. $ 1,721 $ 1,616 $ 5,108 $ 4,740
Basic weighted average shares (in shares) 370 378 371 378
Plus effect of: stock options and restricted stock units (in shares) 1 1 1 1
Diluted weighted average shares (in shares) 371 378 372 378
Basic earnings per share (in dollars per share) $ 4.65 $ 4.28 $ 13.77 $ 12.55
Diluted earnings per share (in dollars per share) $ 4.64 $ 4.27 $ 13.75 $ 12.53
Antidilutive stock options excluded from diluted weighted average shares (in shares) 2 3 3 3