Business Combination - Proforma Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Business Combinations [Abstract]
Revenue	$ 785.5	$ 671.0	$ 1,536.0	$ 1,291.9
Net income attributable to Trimble Inc.	$ 64.1	$ 45.0	$ 138.5	$ 92.1
Basic earnings per share	$ 0.26	$ 0.18	$ 0.56	$ 0.36
Diluted earnings per share	$ 0.25	$ 0.17	$ 0.54	$ 0.36

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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No definition available.

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