XML 22 R29.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Investment Portfolio - Summary of Market Value of Investments (Detail) (USD $) | Sep. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Investment Holdings [Line Items] |  |
Total Investment Portfolio | $ 34,989,899 | $ 18,726,070
Seed Capital Investments |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 29,685,276 | 17,438,325
Seed Capital Investments | Diamond Hill Research Opportunities Fund |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 13,619,318 | 13,305,830
Seed Capital Investments | Diamond Hill Mid Cap Fund |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 10,199,901 | 0
Seed Capital Investments | Diamond Hill Valuation-Weighted 500, L.P. |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 3,259,028 | 3,000,328
Seed Capital Investments | Diamond Hill Global Fund, L.P. |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 1,452,249 | 0
Seed Capital Investments | Diamond Hill Financial Long-Short Fund |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 1,154,780 | 1,131,034
Seed Capital Investments | Diamond Hill Investment Partners, L.P. |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | 0 | 1,133
Investments in Deferred Compensation Plans |  |
Investment Holdings [Line Items] |  |
Total Investment Portfolio | $ 5,304,623 | $ 1,287,745

X
- Details
Name: | us-gaap_InvestmentHoldingsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Sum of the carrying amounts as of the balance sheet date of all investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(h)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph h -Article 7 + Details
Name: | us-gaap_Investments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant