Long-Term Debt - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2019	Dec. 30, 2018
Debt Instrument [Line Items]
Credit Agreement description	On October 18, 2010, the Company, Big 5 Corp. and Big 5 Services Corp. entered into a credit agreement with Wells Fargo Bank, National Association (“Wells Fargo”), as administrative agent, and a syndicate of other lenders, which was amended on October 31, 2011, December 19, 2013 and September 29, 2017 (as so amended, the “Credit Agreement”), and has a maturity date of September 29, 2022.
Maturity date of Credit Agreement	Sep. 29, 2022
First tier of increase to the borrowing capacity	$ 165,000,000
Maximum limit of credit facility	200,000,000
Sublimit for issuances of letters of credit	25,000,000
Sublimit for swingline loans	$ 20,000,000
Percentage of eligible credit card accounts receivables	90.00%
Percentage of the value of eligible inventory	90.00%
Percentage of the value of eligible in-transit inventory	90.00%
Eligible in-transit inventory threshold	$ 10,000,000
Interest rate, description	the applicable margin for base rate loans (as shown below) plus the highest of (a) the Federal funds rate, as in effect from time to time, plus one-half of one percent (0.50%), (b) the LIBO rate, plus one percentage point (1.00%), or (c) the rate of interest in effect for such day as announced from time to time within Wells Fargo as its “prime rate.”
Commitment fee assessed	0.20%
Debt instrument, covenant description	Obligations under the Credit Facility are secured by a general lien and perfected security interest in substantially all of the Company’s assets. The Credit Agreement contains covenants that require the Company to maintain a fixed charge coverage ratio of not less than 1.0:1.0 in certain circumstances, and limit the ability
Events of default, description	The Credit Agreement contains customary events of default, including, without limitation, failure to pay when due principal amounts with respect to the Credit Facility, failure to pay any interest or other amounts under the Credit Facility for five days after becoming due, failure to comply with certain agreements or covenants contained in the Credit Agreement, failure to satisfy certain judgments against the Company, failure to pay when due (or any other default which does or may lead to the acceleration of) certain other material indebtedness in principal amount in excess of $5.0 million, and certain insolvency and bankruptcy events.
Line of Credit Facility default debt minimum amount	$ 5,000,000
Long-term borrowings	45,411,000	$ 65,000,000
Letter of credit commitments	500,000	500,000
Revolving Credit Borrowings [Member]
Debt Instrument [Line Items]
Long-term borrowings	$ 45,400,000	65,000,000
Minimum [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio	100.00%
Federal Funds Rate [Member]
Debt Instrument [Line Items]
Applicable margin in addition to variable rate	0.50%
LIBO Rate [Member]
Debt Instrument [Line Items]
Applicable margin in addition to variable rate	1.00%
Permits to Reduce Aggregate Committed Availability [Member]
Debt Instrument [Line Items]
Revolving credit facility	$ 100,000,000
First Amendment to Credit Agreement [Member]
Debt Instrument [Line Items]
Credit agreement amendment date	Oct. 31, 2011
Second Amendment to Credit Agreement [Member]
Debt Instrument [Line Items]
Credit agreement amendment date	Dec. 19, 2013
Third Amendment to Credit Agreement [Member]
Debt Instrument [Line Items]
Credit agreement amendment date	Sep. 29, 2017
Revolving credit facility	$ 140,000,000
Wells Fargo Bank National Association [Member]
Debt Instrument [Line Items]
Remaining borrowing availability	$ 94,100,000	$ 74,500,000

The date that a current credit agreement amendment is executed.

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A contractual dollar amount threshold applied to the borrowing base calculation.

+ References

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The fixed charge coverage ratio required to be maintained as part of the entity's debt covenant.

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One circumstance of default which describes nonpayment of a minimum amount of material indebtedness, under the terms of the credit agreement.

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The first tier of increase applied to the entity's aggregate committed availability.

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A contractual percentage (threshold) of the amount of eligible credit card accounts receivable which is applied to the borrowing base calculation.

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A contractual percentage (threshold) of the amount of in-transit inventory which is applied to the borrowing base calculation.

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A contractual percentage (threshold) of the amount of eligible inventory, exclusive of in-transit inventory, which is applied to the borrowing base calculation.

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A sublimit established, as part of the credit facility, that applies to issuances of letters of credit.

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A sublimit established, as part of the credit facility, that applies to issuances of swingline loans.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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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.

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Discussion of the facts and amounts pertaining to each failure to comply with an affirmative or negative covenant of a long-term debt instrument, including violating payment terms or an inability to meet certain minimum financial requirements or achieve or maintain certain financial ratios. The discussion would generally be expected to also include whether or not the failure can and will be overcome and a description of the terms of any waivers, including the amount of the waiver and the period of time covered by the waiver, and if reclassification of long-term debt to current has been made in the current balance sheet.

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

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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

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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).

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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.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The carrying value as of the balance sheet date of the noncurrent portion 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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