v3.25.2
Document and Entity Information Document
Aug. 27, 2025
Cover [Abstract]  
Document Type 8-K
Document Period End Date Aug. 27, 2025
Entity Registrant Name COSTAR GROUP, INC.
Entity Central Index Key 0001057352
Amendment Flag false
Entity Incorporation, State or Country Code DE
Entity File Number 0-24531
Entity Tax Identification Number 52-2091509
Entity Address, Address Line One 1201 Wilson Blvd.
Entity Address, City or Town Arlington,
Entity Address, State or Province VA
Entity Address, Postal Zip Code 22209
City Area Code 202
Local Phone Number 346-6500
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock ($0.01 par value)
Trading Symbol CSGP
Security Exchange Name NASDAQ
Entity Emerging Growth Company false