Cover Page - shares	3 Months Ended
	Apr. 04, 2021	May 05, 2021
Cover [Abstract]
Document Type	10-Q
Document Period End Date	Apr. 04, 2021
Entity File Number	001-12561
Entity Registrant Name	BELDEN INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-3601505
Entity Address, Address Line One	1 North Brentwood Boulevard
Entity Address, Address Line Two	15th Floor
Entity Address, City or Town	St. Louis
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63105
City Area Code	314
Local Phone Number	854-8000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity File Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging growth company	false
Entity Shell Company	false
Title of 12(b) Security	Common stock, $0.01 par value
Trading Symbol	BDC
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding		44,738,828
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000913142
Current Fiscal Year End Date	--12-31
Document Quarterly Report	true
Document Transition Report	false