Percentage of remaining interest in StockCross purchased.

No definition available.

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Namespace Prefix:	SIEB_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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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

Face amount or stated value per share of common stock.

+ References

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Organization and Basis of Presentation (Details) - $ / shares	1 Months Ended
	Jan. 25, 2019	Jun. 30, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Common stock, par value		$ 0.01	$ 0.01
StockCross [Member]
Business Acquisition [Line Items]
Equity method investment in StockCross	15.00%
Percentage of remaining interest in StockCross purchased	85.00%
Issuance of common stock in StockCross acquisition	3,298,774