Acquisitions - Schedule of Pro Forma Information (Details) - Thinklogical Holdings LLC - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Oct. 01, 2017	Oct. 02, 2016	Oct. 01, 2017	Oct. 02, 2016
Business Acquisition [Line Items]
Revenues	$ 621,745	$ 616,760	$ 1,792,614	$ 1,772,202
Net income (loss) attributable to Belden common stockholders	$ (5,128)	$ 34,564	$ 37,097	$ 85,588
Diluted income (loss) per share attributable to Belden common stockholders (in usd per share)	$ (0.12)	$ 0.81	$ 0.87	$ 2.01

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

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 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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