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Business and Organization | 9 Months Ended
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Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Business and Organization | Business and Organization Diamond Hill Investment Group, Inc. (the "Company"), an Ohio corporation, derives its consolidated revenues and net income from investment advisory and fund administration services. Diamond Hill Capital Management, Inc. ("DHCM"), an Ohio corporation, is a wholly owned subsidiary of the Company and a registered investment adviser. DHCM is the investment adviser to the Diamond Hill Funds (the "Funds"), a series of open-end mutual funds, private investment funds ("Private Funds"), an exchange traded fund (the "ETF"), and other institutional accounts. In addition, DHCM is administrator for the Funds.

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- Definition The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -URI http://asc.fasb.org/topic&trid=2122149 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -URI http://asc.fasb.org/topic&trid=2197479 + Details
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