Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss), Net of Tax (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jul. 03, 2022	Apr. 03, 2022	Jul. 04, 2021	Apr. 04, 2021	Jul. 03, 2022
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 947,595	$ 956,082	$ 845,460	$ 757,051	$ 956,082
Net current period other comprehensive income attributable to Belden	52,126	3,955	(21,494)	53,528
Ending balance	1,049,083	947,595	874,098	845,460	1,049,083
Accumulated Other  Comprehensive Income (Loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(66,638)	(70,566)	(138,126)	(191,851)	(70,566)
Other comprehensive income attributable to Belden before reclassifications					58,712
Amounts reclassified from accumulated other comprehensive income (loss)					(2,633)
Net current period other comprehensive income attributable to Belden	52,151	3,928	(21,265)	53,725	56,079
Ending balance	(14,487)	(66,638)	$ (159,391)	$ (138,126)	(14,487)
Foreign Currency Translation Component
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		(41,468)			(41,468)
Other comprehensive income attributable to Belden before reclassifications					58,712
Amounts reclassified from accumulated other comprehensive income (loss)					(3,007)
Net current period other comprehensive income attributable to Belden					55,705
Ending balance	14,237				14,237
Pension and Other  Postretirement Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance		$ (29,098)			(29,098)
Other comprehensive income attributable to Belden before reclassifications					0
Amounts reclassified from accumulated other comprehensive income (loss)					374
Net current period other comprehensive income attributable to Belden					374
Ending balance	$ (28,724)				$ (28,724)