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Revenue from Contracts with Customers Revenue from Contracts with Customers (Schedule of Consumer Brokerage Services) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consumer Brokerage Services [Line Items]
Brokerage Commissions Revenue	$ 15,095	$ 15,804	$ 15,807
Commission Income [Member]
Consumer Brokerage Services [Line Items]
Brokerage Commissions Revenue	8,002	9,071	8,956
Managed Account Services [Member]
Consumer Brokerage Services [Line Items]
Brokerage Commissions Revenue	$ 7,093	$ 6,733	$ 6,851

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- Definition

[Line Items] for Disclosure of information of fees earned from consumer brokerage services from contracts with customers.

+ References

No definition available.

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- Definition

Amount of commission revenue from buying and selling securities on behalf of customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 05
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=68070981&loc=d3e40544-110947

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(a),(b))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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