Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Schedule of Components of Other Comprehensive Income (Loss), Net of Tax (Details) $ in Thousands	3 Months Ended
	Mar. 30, 2025 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,294,736
Other comprehensive loss attributable to Belden before reclassifications	(37,360)
Amounts reclassified from accumulated other comprehensive loss	210
Net current period other comprehensive loss attributable to Belden	(37,150)
Ending balance	1,222,507
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3,532)
Ending balance	(40,682)
Foreign Currency Translation Component
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	3,129
Other comprehensive loss attributable to Belden before reclassifications	(37,360)
Amounts reclassified from accumulated other comprehensive loss	0
Net current period other comprehensive loss attributable to Belden	(37,360)
Ending balance	(34,231)
Pension and Other  Postretirement Benefit Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(6,661)
Other comprehensive loss attributable to Belden before reclassifications	0
Amounts reclassified from accumulated other comprehensive loss	210
Net current period other comprehensive loss attributable to Belden	210
Ending balance	$ (6,451)