Expense for self-insurance claims.

No definition available.

Name:	SIEB_ExpenseForSelfInsuranceClaims
Namespace Prefix:	SIEB_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Health claim reinsurance limit per employee.

+ References

No definition available.

+ Details

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Namespace Prefix:	SIEB_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

+ References

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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

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Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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Commitments, Contingencies and Other (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended
	Jan. 22, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Health claim reinsurance limit per employee		$ 50,000
Expense for self-insurance claims		291,000	$ 210,000
Accrual for self-insurance claims		88,000
Interest expense		52,000	60,000
Aggregate amount in legal matters	$ 900,000
Supervisory Requirements [Member] \| StockCross [Member]
Aggregate amount in legal matters		300,000
BMO Harris Bank and Texas Capital Bank [Member]
Available lines of credit		15,000,000
Interest expense		$ 14,000	$ 16,000
BMO Harris Bank and Texas Capital Bank [Member] \| MSCO [Member]
Line of credit				$ 15,000,000