Summary of Investments (Narrative) (Details) $ in Thousands	1 Months Ended
Dec. 31, 2019 USD ($) date	Sep. 30, 2020 USD ($)
Investments, Debt and Equity Securities [Abstract]
Trading securities	$ 15,256	$ 14,811
Remaining potential contractual obligation		10,284
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 fair value		$ 24,035

Investment, Lockup, Minimum Notice Period

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Investment, Lockup Period

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Investment, Number Of Repurchase Dates

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Limited Liability Partnership Investment Fund, Fair Value Disclosure

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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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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=121586364&loc=d3e3213-108585

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

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