Selected Quarterly Financial Data (Schedule Of Selected Quarterly Financial Data) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 02, 2015	Oct. 03, 2014	Jul. 04, 2014	Apr. 04, 2014	Jan. 03, 2014	Sep. 27, 2013	Jun. 28, 2013	Mar. 29, 2013	Jan. 02, 2015		Jan. 03, 2014		Dec. 28, 2012
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 563,830	$ 584,796	$ 642,199	$ 604,721	$ 599,218	$ 556,502	$ 576,293	$ 556,111	$ 2,395,546	[1]	$ 2,288,124	[1]	$ 2,040,113	[1]
Gross margin	292,608	316,773	354,571	326,892	319,454	295,053	302,401	286,914	1,290,844		1,203,822		1,046,177
Net income attributable to Trimble Navigation Ltd.	$ 55,828	$ 11,832	$ 77,834	$ 68,624	$ 59,997	$ 54,469	$ 54,581	$ 49,808	$ 214,118		$ 218,855		$ 191,060
Basic net income per share	$ 0.22	$ 0.05	$ 0.30	$ 0.26	$ 0.23	$ 0.21	$ 0.21	$ 0.20	$ 0.82		$ 0.85		$ 0.76
Diluted net income per share	$ 0.21	$ 0.04	$ 0.29	$ 0.26	$ 0.23	$ 0.21	$ 0.21	$ 0.19	$ 0.81		$ 0.84		$ 0.74

[1] Revenue is attributed to countries based on the location of the customer.