Acquisitions - Schedule of Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Apr. 01, 2018	Apr. 02, 2017
Snell Advanced Media
Business Acquisition [Line Items]
Revenues	$ 614,184	$ 579,371
Net income (loss) attributable to Belden common stockholders	$ (1,072)	$ 979
Diluted income (loss) per share attributable to Belden common stockholders (in usd per share)	$ (0.03)	$ 0.02
Thinklogical Holdings LLC
Business Acquisition [Line Items]
Revenues		$ 555,636
Net income (loss) attributable to Belden common stockholders		$ 12,880
Diluted income (loss) per share attributable to Belden common stockholders (in usd per share)		$ 0.30

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.

No definition available.

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- Definition

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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