v3.25.1
Cover Page Cover Page
Jun. 12, 2025
Cover [Abstract]  
Entity Central Index Key 0000909108
Title of 12(b) Security Common stock, no par value
Document Period End Date Jun. 12, 2025
Entity Registrant Name DIAMOND HILL INVESTMENT GROUP, INC.
Entity Incorporation, State or Country Code OH
Document Type 8-K
Entity File Number 000-24498
Entity Tax Identification Number 65-0190407
Entity Address, Address Line One 325 John H. McConnell Blvd, Suite 200
Entity Address, City or Town Columbus
Entity Address, State or Province OH
Entity Address, Postal Zip Code 43215
City Area Code 614
Local Phone Number 255-3333
Trading Symbol DHIL
Security Exchange Name NASDAQ
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Amendment Flag false