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Investments Schedule of Equity Method Investment Ownership (Details) $ in Millions | Mar. 31, 2025 USD ($)
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Schedule of Equity Method Investments [Line Items] |
Equity method investment, deferred compensation plans | $ 8.3
DMHF |
Schedule of Equity Method Investments [Line Items] |
Ownership percentage | 85.00%
Large Cap Fund |
Schedule of Equity Method Investments [Line Items] |
Ownership percentage | 39.00%
Diamond Hill International Fund |
Schedule of Equity Method Investments [Line Items] |
Ownership percentage | 38.00%

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