Acquisitions - Schedule of Pro Forma Information (Details) - OTN Systems N.V. - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Apr. 04, 2021	Mar. 29, 2020
Business Acquisition [Line Items]
Revenues	$ 536,780	$ 468,700
Net income from continuing operations attributable to Belden common stockholders	$ 28,216	$ 9,697
Diluted income from continuing operations per share attributable to Belden common stockholders	$ 0.63	$ 0.21

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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

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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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