Acquisitions - Schedule of Pro Forma Information (Details) - Opterna International Corp. $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares
Business Acquisition [Line Items]
Revenues	$ 508,756
Net income from continuing operations attributable to Belden common stockholders	$ 19,243
Diluted income from continuing operations per share attributable to Belden common stockholders \| $ / shares	$ 0.49

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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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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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