CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2025	Sep. 29, 2024	Sep. 28, 2025	Sep. 29, 2024
Income Statement [Abstract]
Revenues	$ 698,221	$ 654,926	$ 1,995,074	$ 1,794,937
Cost of sales	(435,023)	(410,922)	(1,227,468)	(1,122,531)
Gross profit	263,198	244,004	767,606	672,406
Selling, general and administrative expenses	(139,415)	(126,976)	(402,859)	(357,241)
Research and development expenses	(33,859)	(27,941)	(96,216)	(83,397)
Amortization of intangibles	(13,636)	(13,738)	(40,381)	(34,487)
Operating income	76,288	75,349	228,150	197,281
Interest expense, net	(11,562)	(10,855)	(33,866)	(27,454)
Non-operating pension benefit (cost)	(398)	286	(1,203)	747
Loss related to revolver refinancing	(76)	0	(76)	0
Income before taxes	64,252	64,780	193,005	170,574
Income tax expense	(7,562)	(11,091)	(23,372)	(30,542)
Net income	56,690	53,689	169,633	140,032
Less: Net loss attributable to noncontrolling interest	0	(3)	0	(17)
Net income attributable to Belden stockholders	$ 56,690	$ 53,692	$ 169,633	$ 140,049
Weighted average number of common shares and equivalents:
Basic (in shares)	39,516	40,798	39,728	40,825
Diluted (in shares)	40,137	41,417	40,324	41,371
Basic income per share attributable to Belden stockholders (in usd per share)	$ 1.43	$ 1.32	$ 4.27	$ 3.43
Diluted income per share attributable to Belden stockholders (in usd per share)	$ 1.41	$ 1.30	$ 4.21	$ 3.39
Comprehensive income attributable to Belden	$ 48,064	$ 23,760	$ 83,961	$ 126,175
Common stock dividends declared per share (in usd per share)	$ 0.05	$ 0.05	$ 0.15	$ 0.15