XML 11 R1.htm IDEA: XBRL DOCUMENT v3.24.0.1
Cover Page - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Jan. 31, 2024
Jun. 30, 2023
Cover [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Fiscal Year Focus 2023    
Document Fiscal Period Focus FY    
Document Annual Report true    
Document Transition Report false    
Current Fiscal Year End Date --12-31    
Document Period End Date Dec. 31, 2023    
Entity File Number 1-13879    
Entity Registrant Name INNOSPEC INC.    
Entity Central Index Key 0001054905    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 98-0181725    
Entity Address, Postal Zip Code 80112    
City Area Code 303    
Local Phone Number 792 5554    
Security Exchange Name NASDAQ    
Title of 12(b) Security Common stock    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   24,867,989  
Entity Address, Address Line One 8310 South Valley Highway    
Entity Address, Address Line Two Suite 350    
Entity Address, City or Town Englewood    
Entity Address, State or Province CO    
Trading Symbol IOSP    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer Yes    
Entity Public Float     $ 1,349
Documents Incorporated by Reference

DOCUMENTS INCORPORATED BY REFERENCE

Portions of Innospec Inc.’s Proxy Statement for the Annual Meeting of Stockholders to be held on May 10, 2024 are incorporated by reference into Part III of this Form 10-K.

   
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction [Flag] false    
Auditor Name PricewaterhouseCoopers LLP    
Auditor Firm ID 876    
Auditor Location Manchester, United Kingdom