Comprehensive Income and Accumulated Other Comprehensive Income (Loss) - Total Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 29, 2024	Jun. 30, 2024	Mar. 31, 2024	Oct. 01, 2023	Jul. 02, 2023	Apr. 02, 2023	Sep. 29, 2024	Oct. 01, 2023
Equity [Abstract]
Net income	$ 53,689	$ 49,034	$ 37,309	$ 72,327	$ 68,775	$ 62,945	$ 140,032	$ 204,047
Foreign currency translation adjustments, net of tax	(29,859)			21,852			(13,653)	257
Adjustments to pension and postretirement liability, net of tax	(73)			(284)			(221)	(848)
Total comprehensive income	23,757			93,895			126,158	203,456
Less: Comprehensive loss attributable to noncontrolling interests	(3)			(20)			(17)	(241)
Comprehensive income attributable to Belden	$ 23,760			$ 93,915			$ 126,175	$ 203,697