v3.25.1
Document and Entity Information Document
Apr. 22, 2025
Cover [Abstract]  
Document Type 8-K
Document Period End Date Apr. 22, 2025
Entity Registrant Name MSCI Inc.
Entity Central Index Key 0001408198
Amendment Flag false
Entity Tax Identification Number 13-4038723
Entity Address, Address Line One 7 World Trade Center,
Entity Address, Address Line Two 250 Greenwich Street, 49th Floor,
Entity Address, City or Town New York,
Entity Address, State or Province NY
Entity Address, Postal Zip Code 10007
City Area Code 212
Local Phone Number 804-3900
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, par value $0.01 per share
Trading Symbol MSCI
Security Exchange Name NYSE
Entity Emerging Growth Company false
Entity Incorporation, State or Country Code DE
Entity File Number 001-33812