Earnings Per Share (Schedule Of Computation Of Earnings Per Share And Effect On Weighted-Average Number Of Shares) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Numerator:
Net income attributable to Trimble Inc.	$ 124.0	$ 84.7	$ 377.4	$ 209.6
Denominator:
Weighted average number of common shares used in basic earnings per share (in shares)	251,800	250,700	251,500	250,400
Effect of dilutive securities (in shares)	2,700	2,100	2,800	1,500
Weighted average number of common shares and dilutive potential common shares used in diluted earnings per share (in shares)	254,500	252,800	254,300	251,900
Basic earnings per share (in dollars per share)	$ 0.49	$ 0.34	$ 1.50	$ 0.84
DIluted earnings per share (in dollars per share)	$ 0.49	$ 0.34	$ 1.48	$ 0.83
Antidilutive weighted average (in shares)	100	300	0	1,100