Acquisitions - Pro Forma Effect on Operating Results (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Tripwire [Member]
Business Acquisition [Line Items]
Revenues	$ 2,354,191	$ 2,405,198
Income (loss) from continuing operations	$ 92,104	$ 23,302
Diluted income per share from continuing operations attributable to Belden stockholders	$ 2.14	$ 0.53
Grass Valley and Prosoft [Member]
Business Acquisition [Line Items]
Revenues		$ 2,401,200	$ 2,420,099
Income (loss) from continuing operations		$ 67,956	$ 66,874
Diluted income per share from continuing operations attributable to Belden stockholders		$ 1.54	$ 1.49

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 income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock 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=56956515&loc=d3e1392-128463

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- Definition

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

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

+ References

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