Investments in Securities and Fair Value Investments in Securities (Schedule of Cost-method Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Measurement Alternative Investments
Beginning of Period	$ 6,589	$ 5,439
Amounts Impairment	0	0
Observable Changes	0	0
Purchases and Additional Commitments Paid	2,241	1,486
Sales, Returns of Capital, and Other Reductions	(931)	(336)
End of Period	$ 7,899	$ 6,589

Other Equity Investments, Impairment

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- Definition

Other Equity Investments, Observable Changes

+ References

No definition available.

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- Definition

Other Equity Investments, Purchases and Additional Commitments Paid

+ References

No definition available.

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- Definition

Other Equity Investments, Sales, Returns of Capital, and Other Reductions

+ References

No definition available.

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- Definition

Fair value portion of investments in an entity not consolidated. Includes, but is not limited to, investments in an entity that is affiliated with the reporting entity by means of direct or indirect ownership, an entity in which the reporting entity shares control of the entity with another party or group, an entity which the company has significant influence, but does not have control and subsidiaries that are not required to be consolidated and are accounted for using the equity or cost method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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