Investments in Securities and Fair Value Investments in Securities (Schedule of Variable Interest Entities) (Details) - Other Investments $ in Thousands	Dec. 31, 2019 USD ($)
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Value	$ 11,816
Variable Interest Entity, Nonconsolidated, Estimated Fair Value	12,110
Variable Interest Entity, Reporting Entity Involvement, Maximum Potential Loss	17,355
Variable Interest Entity, Not Primary Beneficiary, Tax Credit LP
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Value	228
Variable Interest Entity, Nonconsolidated, Estimated Fair Value	228
Variable Interest Entity, Reporting Entity Involvement, Maximum Potential Loss	1,325
Variable Interest Entity, Not Primary Beneficiary, Real Estate LLC or LP
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Value	5,405
Variable Interest Entity, Nonconsolidated, Estimated Fair Value	5,898
Variable Interest Entity, Reporting Entity Involvement, Maximum Potential Loss	7,075
Variable Interest Entity, Not Primary Beneficiary, Small Business Investment LLCs or LPs
Variable Interest Entity [Line Items]
Variable Interest Entity, Nonconsolidated, Carrying Value	6,183
Variable Interest Entity, Nonconsolidated, Estimated Fair Value	5,984
Variable Interest Entity, Reporting Entity Involvement, Maximum Potential Loss	$ 8,955

Estimated fair value amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

No definition available.

+ Details

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5747-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=118582676&loc=d3e5728-111685

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