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Business and Organization | 9 Months Ended
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Sep. 30, 2017
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. Beacon Hill Fund Services, Inc. (“BHFS”) and BHIL Distributors, Inc. (“BHIL”), collectively operated as "Beacon Hill," were operating subsidiaries of the Company. The Company sold Beacon Hill on July 31, 2016 (See Note 10). Prior to the sale, Beacon Hill provided compliance, treasury, underwriting and other fund administration services to investment advisers and mutual 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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