Custom Element.

No definition available.

Name:	rily_InterestExpenseIncludingSuccessFees
Namespace Prefix:	rily_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of 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

No definition available.

+ Details

Name:	rily_LineOfCreditFacilityBorrowingCapacityPercentage
Namespace Prefix:	rily_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amended 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

No definition available.

+ Details

Name:	rily_LineOfCreditFacilityMaximumBorrowingCapacityAmended
Namespace Prefix:	rily_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Before amended 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

No definition available.

+ Details

Name:	rily_LineOfCreditFacilityMaximumBorrowingCapacityBeforeAmended
Namespace Prefix:	rily_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects when the amended credit facility terminates, which may be presented in a variety of ways (year, month and year, day, month and year, quarter).

+ References

No definition available.

+ Details

Name:	rily_LineOfCreditMaturityDateAmended
Namespace Prefix:	rily_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Custom Element.

+ References

No definition available.

+ Details

Name:	rily_SuccessFees
Namespace Prefix:	rily_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

+ Details

Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_CreditFacilityAxis=rily_AccountsReceivableLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=rily_UkCreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

CREDIT FACILITIES (Details Textual) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 19, 2014	Jul. 15, 2013
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,385	$ 100,000
Line of Credit Facility, Expiration Date		Jul. 15, 2018
Line of Credit Facility, Interest Rate Description		The interest rate for each revolving credit advance under the Credit Agreement is, subject to certain terms and conditions, equal to the LIBOR plus a margin of 2.25% to 3.25% (3.165% at December 31, 2013) depending on the type of advance and the percentage such advance represents of the related transaction for which such advance is provided.
Interest Expense, Debt		325us-gaap_InterestExpenseDebt
Line Of Credit Maturity Date Amended			Feb. 03, 2015
Long-term Line of Credit	8,553us-gaap_LineOfCredit	333us-gaap_LineOfCredit
Success fees	162rily_SuccessFees	292rily_SuccessFees	292rily_SuccessFees
Interest expense including success fees	400	532	532
Outstanding amount	18,506	5,710
Minimum [Member]
Line of Credit Facility [Line Items]
Line Of Credit Facility Borrowing Capacity Percentage	5.00%
Maximum [Member]
Line of Credit Facility [Line Items]
Line Of Credit Facility Borrowing Capacity Percentage	20.00%
Accounts Receivable Line Of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Interest Rate Description	prime rate plus 2% (6% at December 31, 2014), payable monthly in arrears.
Interest Expense, Debt	46	90	112
Line Of Credit Facility Borrowing Capacity Percentage			85.00%
Line Of Credit Facility Maximum Borrowing Capacity Before Amended			2,000
Line Of Credit Facility Maximum Borrowing Capacity Amended			3,000
UK Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 50,000	$ 100,000