Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 03, 2022	Apr. 04, 2021
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 956,082	$ 757,051
Net current period other comprehensive income attributable to Belden	3,955	53,528
Ending balance	947,595	845,460
Accumulated Other  Comprehensive Income (Loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(70,566)	(191,851)
Other comprehensive income attributable to Belden before reclassifications	6,742
Amounts reclassified from accumulated other comprehensive income (loss)	(2,814)
Net current period other comprehensive income attributable to Belden	3,928	53,725
Ending balance	(66,638)	$ (138,126)
Foreign Currency Translation Component
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(41,468)
Other comprehensive income attributable to Belden before reclassifications	6,742
Amounts reclassified from accumulated other comprehensive income (loss)	(3,007)
Net current period other comprehensive income attributable to Belden	3,735
Ending balance	(37,733)
Pension and Other  Postretirement Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(29,098)
Other comprehensive income attributable to Belden before reclassifications	0
Amounts reclassified from accumulated other comprehensive income (loss)	193
Net current period other comprehensive income attributable to Belden	193
Ending balance	$ (28,905)