Joint Ventures (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 01, 2011	Jul. 02, 2010	Jul. 01, 2011	Jul. 02, 2010	Dec. 31, 2010
Caterpillar Trimble Control Technologies LLC [Member]
Proportionate share of net income (loss)	$ 3.4	$ 2.7	$ 5.8	$ 4.4
Amount of dividend received from related party	7.5	5.0	7.5	5.0
Carrying amount of investment	7.2		7.2		8.9
Amount received as reimbursement of employee-related cost	3.7	2.7	7.6	5.6
Amount receivables from related party	7.3		7.3		4.4
Amount due to related party	9.1		9.1		5.7
Caterpillar [Member]
Percentage of ownership of joint venture with equal voting rights	50.00%		50.00%
Caterpillar Distribution Channel [Member]
Revenue recorded for manufacturing of products sold by the company to related party	1.3	0.9	2.7	1.8
Cost of sales recorded for manufacturing of products sold by the company to related party	1.3	0.8	2.7	1.7
Nikon-Trimble Co. Ltd [Member]
Proportionate share of net income (loss)	0.3	(0.5)	1.0	(1.3)
Amount of dividend received from related party	0	0	0	0
Carrying amount of investment	16.5		16.5		15.5
Revenue recorded for manufacturing of products sold by the company to related party	3.9	3.9	8.3	8.5
Cost of sales recorded for manufacturing of products sold by the company to related party	2.2	2.6	4.7	5.4
Purchase of product from related party	6.0	2.9	11.9	8.3
Amount receivables from related party	3.9		3.9		3.5
Amount due to related party	6.0		6.0		7.0
Nikon Corporation [Member]
Percentage of ownership of joint venture with equal voting rights	50.00%		50.00%
Trimble Navigation Ltd [Member]
Percentage of ownership of joint venture with equal voting rights	50.00%		50.00%
Cost of sales recorded for manufacturing of products sold by the company to related party	$ 10.6	$ 8.5	$ 18.5	$ 14.6