v3.25.2
Document And Entity Information
Jul. 31, 2025
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Jul. 31, 2025
Entity Registrant Name ICF International, Inc.
Entity Central Index Key 0001362004
Entity Emerging Growth Company false
Entity File Number 001-33045
Entity Incorporation, State or Country Code DE
Entity Tax Identification Number 22-3661438
Entity Address, Address Line One 1902 Reston Metro Plaza
Entity Address, City or Town Reston
Entity Address, State or Province VA
Entity Address, Postal Zip Code 20190
City Area Code 703
Local Phone Number 934-3000
Entity Information, Former Legal or Registered Name Not Applicable
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock
Trading Symbol ICFI
Security Exchange Name NASDAQ