Ownership Interests in and Advances to Partner Companies and Funds - Carrying Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Investments In And Advances To Affiliates [Line Items]
Equity method investments	$ 35,263	$ 64,489
Cost method investments	27,494	15,771
Advances to partner companies	16,888	15,325
Investments in and advance to affiliates, subsidiaries, associates, and joint ventures	79,645	95,585
Partner companies
Investments In And Advances To Affiliates [Line Items]
Equity method investments	34,871	64,097
Cost method investments	27,031	15,260
Private equity funds
Investments In And Advances To Affiliates [Line Items]
Equity method investments	392	392
Cost method investments	$ 463	$ 511

Long-Term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership. This does not include advances to clients.

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+ References

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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