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 Millions, $ in Millions	12 Months Ended
	Jan. 01, 2021	Jan. 03, 2020	Dec. 28, 2018
Numerator:
Net income attributable to Trimble Inc.	$ 389.9	$ 514.3	$ 282.8
Denominator:
Weighted average number of common shares used in basic earnings per share (in shares)	250.5	250.8	250.0
Effect of dilutive securities (in shares)	1.8	2.1	3.4
Weighted average number of common shares and dilutive potential common shares used in diluted earnings per share (in shares)	252.3	252.9	253.4
Basic (in dollars per share)	$ 1.56	$ 2.05	$ 1.13
Diluted (in dollars per share)	$ 1.55	$ 2.03	$ 1.12
Antidilutive shares (in shares)	0.5	0.1	0.7