Summary of Investments (Narrative) (Details) $ in Thousands	1 Months Ended
Dec. 31, 2019 USD ($) date	Mar. 31, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Trading securities	$ 15,256	$ 11,208
Remaining potential contractual obligation		$ 12,583
Investment in limited liability partnership investment fund	$ 25,000
Lockup period	3 years
Minimum notice period	60 days
Number of possible repurchase dates \| date	4

Investment, Lockup, Minimum Notice Period

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Investment, Lockup Period

+ References

No definition available.

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- Definition

Investment, Number Of Repurchase Dates

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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- References

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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