v3.25.2
Document And Entity Information
6 Months Ended
Jun. 30, 2025
shares
Cover [Abstract]  
Document Type 10-Q
Document Fiscal Period Focus Q2
Document Quarterly Report true
Document Period End Date Jun. 30, 2025
Document Transition Report false
Amendment Flag false
Document Fiscal Year Focus 2025
Current Fiscal Year End Date --12-31
Entity File Number 1-32190
Entity Registrant Name NEWMARKET CORPORATION
Entity Central Index Key 0001282637
Entity Incorporation, State or Country Code VA
Entity Tax Identification Number 20-0812170
Entity Address, Address Line One 330 South Fourth Street
Entity Address, City or Town Richmond,
Entity Address, State or Province VA
Entity Address, Postal Zip Code 23219-4350
City Area Code 804
Local Phone Number 788-5000
Title of 12(b) Security Common Stock, with no par value
Trading Symbol NEU
Security Exchange Name NYSE
Entity Current Reporting Status Yes
Entity Interactive Data Current Yes
Entity Filer Category Large Accelerated Filer
Small Business Company false
Emerging Growth Company false
Entity Shell Company false
Entity Common Stock, Shares Outstanding 9,396,621