Equity Method Investment, Deferred Compensation Plan Investments

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Investments - Textual (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt and Equity Securities, FV-NI [Line Items]
Equity Method Investment, Deferred Compensation Plan Investments	$ 3,800,000
Company sponsored equity method investments	$ 24,105,808	$ 13,627,360
Micro Cap Fund LP
Debt and Equity Securities, FV-NI [Line Items]
Equity method investment	85.00%
DMHF
Debt and Equity Securities, FV-NI [Line Items]
Equity method investment		87.00%
Company sponsored equity method investments	$ 13,100,000	$ 13,600,000
Diamond Hill Core Bond Fund \| Minimum
Debt and Equity Securities, FV-NI [Line Items]
Equity method investment			20.00%
Diamond Hill Core Bond Fund \| Maximum
Debt and Equity Securities, FV-NI [Line Items]
Equity method investment			50.00%
Large Cap Concentrated Fund
Debt and Equity Securities, FV-NI [Line Items]
Equity method investment	48.00%
Securities held in Consolidated Funds
Debt and Equity Securities, FV-NI [Line Items]
Trading Investments	$ 54,740,993	73,855,204
Parent \| Securities held in Consolidated Funds
Debt and Equity Securities, FV-NI [Line Items]
Trading Investments	37,500,000	55,800,000
Redeemable Noncontrolling Interest \| Securities held in Consolidated Funds
Debt and Equity Securities, FV-NI [Line Items]
Trading Investments	$ 17,200,000	$ 18,100,000