Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Investments at fair value	$ 134,568	$ 149,987
Investments at cost	611	1,084
Investments accounted for under the equity method	6,363	7,070
Total investments	141,542	158,141
Estimated fair market value of investments carried at cost	600
Investments attributable to noncontrolling interests
Schedule of Investments [Line Items]
Total investments	(66,516)	(75,245)
Investments attributable to parent
Schedule of Investments [Line Items]
Total investments	$ 75,026	$ 82,896

Investments, excluding financial instruments owned.

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Investments not included in financial instruments owned that are carried at fair value. Examples may include, investments in private companies and partnerships, registered mutual funds, warrants of public and private companies and private company debt.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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Fair value portion of investments accounted under the cost method.

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 323
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-Publisher FASB
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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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