Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Oct. 02, 2016
Accounting Policies [Abstract]
Consolidation	Consolidation The accompanying Interim Financial Statements include the accounts of Big 5 Sporting Goods Corporation, Big 5 Corp. and Big 5 Services Corp. Intercompany balances and transactions have been eliminated in consolidation.
Reporting Period	Reporting Period The Company follows the concept of a 52-53 week fiscal year, which ends on the Sunday nearest December 31. Fiscal year 2016 is comprised of 52 weeks and ends on January 1, 2017. Fiscal year 2015 was comprised of 53 weeks and ended on January 3, 2016. The four quarters of fiscal 2016 are each comprised of 13 weeks. The first three quarters in fiscal 2015 were each comprised of 13 weeks, and the fourth quarter of fiscal 2015 was comprised of 14 weeks.
Recently Adopted Accounting Updates	Recently Adopted Accounting Updates In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2015-03, Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs, which requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU requires retrospective adoption and is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. In August 2015, the FASB issued ASU No. 2015-15, Interest—Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements—Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EITF Meeting, which amends Subtopic 835-30 to allow an entity to defer and present debt issuance costs associated with line-of-credit arrangements as an asset and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether or not there are any outstanding borrowings on the line-of-credit arrangement. The effective date of ASU No. 2015-03 was unaffected by the issuance of ASU No. 2015-15. The adoption of ASU No. 2015-03 and ASU No. 2015-15 had no impact on the Company’s consolidated financial statements as the Company continues to classify debt issuance costs related to its line-of-credit arrangement in other assets. In April 2015, the FASB issued ASU No. 2015-05, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement, which provides guidance to customers about whether a cloud computing arrangement includes a software license. If an arrangement includes a software license, the customer should account for the fees related to the software license element in a manner consistent with licenses of other intangible assets. If the arrangement does not include a license, the arrangement will be accounted for as a service contract. This ASU permits either retrospective or prospective adoption and is effective for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The Company adopted ASU No. 2015-05 prospectively during the first quarter of fiscal 2016, and such adoption did not have a material impact on the Company’s consolidated financial statements. In July 2015, the FASB issued ASU No. 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory, which requires all inventory, other than inventory measured at last-in, first-out (“LIFO”) or the retail inventory method, to be measured at the lower of cost and net realizable value. Net realizable value represents the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. This ASU is effective for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The amendments in this ASU should be applied prospectively with earlier application permitted as of the beginning of an interim or annual reporting period. The Company elected to early-adopt ASU No. 2015-11 during the first quarter of fiscal 2016, and such early adoption did not have a material impact on the Company’s consolidated financial statements. In November 2015, the FASB issued ASU No. 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes, which requires that deferred tax liabilities and assets be classified as noncurrent in a classified balance sheet. Prior to the issuance of this guidance, deferred tax liabilities and assets were required to be separately classified into a current amount and a noncurrent amount in the balance sheet. The new accounting guidance represents a change in accounting principle and the standard is effective for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years, with earlier application permitted as of the beginning of an interim or annual reporting period. The Company elected to early-adopt ASU No. 2015-17 during the first quarter of fiscal 2016 and retrospectively apply the presentation. Accordingly, deferred income tax assets in the amount of $11.1 million, which were previously classified as current assets as of January 3, 2016, were reclassified to non-current deferred income tax assets on the Company's consolidated balance sheet to conform to current year presentation.
Recently Issued Accounting Updates	Recently Issued Accounting Updates In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which includes amendments that create Topic 606 and supersede the revenue recognition requirements in Topic 605, Revenue Recognition, including most industry-specific revenue recognition guidance throughout the Industry Topics of the Codification. In addition, the amendments supersede the cost guidance in Subtopic 605-35, Revenue Recognition—Construction-Type and Production-Type Contracts, and create new Subtopic 340-40, Other Assets and Deferred Costs—Contracts with Customers. In summary, the core principle of Topic 606 is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The amendments in ASU No. 2014-09 were originally effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application was not permitted. On July 9, 2015, the FASB decided to defer for one year the effective date of ASU No. 2014-09, while also deciding to permit early application. With these changes, ASU No. 2014-09 will become effective for annual reporting periods (including interim reporting periods within those periods) beginning after December 15, 2017, with early application permitted as of the original effective date in ASU No. 2014-09 (i.e., annual reporting periods beginning after December 15, 2016). The Company is evaluating the future impact of this ASU, including the deferral decisions reached by the FASB, on the consolidated financial statements. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), which requires lessees to recognize on the balance sheet assets and liabilities for leases with lease terms of more than 12 months. Consistent with GAAP, the recognition, measurement, and presentation of expenses and cash flows arising from a lease by a lessee will depend primarily on its classification as a finance or operating lease. However, unlike current GAAP—which requires only capital leases to be recognized on the balance sheet—the new ASU will require both types of leases to be recognized on the balance sheet. The ASU will take effect for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. This ASU shall be applied at the beginning of the earliest period presented using the modified retrospective approach, which includes a number of practical expedients that an entity may elect to apply. Early application of ASU No. 2016-02 is permitted. The Company is evaluating the future impact of this ASU on the consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Compensation—Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting, which includes multiple provisions intended to simplify various aspects of the accounting for share-based payments, including treatment of excess tax benefits and forfeitures, as well as consideration of minimum statutory tax withholding requirements. The ASU will take effect for public companies for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2016, with early application permitted as of the beginning of an interim or annual reporting period. The Company is evaluating the future impact of this ASU on the consolidated financial statements. Other recently issued accounting updates are not expected to have a material impact on the Company’s consolidated financial statements.
Use of Estimates	Use of Estimates Management has made a number of estimates and assumptions relating to the reporting of assets, liabilities and stockholders’ equity and the disclosure of contingent assets and liabilities as of the date of the Interim Financial Statements and reported amounts of revenue and expense during the reporting period to prepare these Interim Financial Statements in conformity with GAAP. Certain items subject to such estimates and assumptions include the carrying amount of merchandise inventories, property and equipment, and goodwill; valuation allowances for receivables, sales returns and deferred income tax assets; estimates related to gift card breakage and the valuation of share-based compensation awards; and obligations related to asset retirements, litigation, self-insurance liabilities and employee benefits. Actual results could differ significantly from these estimates under different assumptions and conditions.
Revenue Recognition	Revenue Recognition The Company recognizes revenue from retail sales at the point of sale through its retail stores. For e-commerce sales, revenue is recognized when the merchandise is delivered to the customer. Shipping and handling fees, when billed to customers for e-commerce sales, are included in net sales and the related shipping and handling costs are included in cost of sales. An allowance for sales returns is estimated based upon historical experience and recorded as a reduction in sales in the relevant period. Cash received from the sale of gift cards is recorded as a liability, and revenue is recognized upon the redemption of the gift card or when it is determined that the likelihood of redemption is remote (“gift card breakage”) and no liability to relevant jurisdictions exists. The Company does not sell gift cards that carry expiration dates. The Company determines the gift card breakage rate based upon historical redemption patterns and recognizes gift card breakage on a straight-line basis over the estimated gift card redemption period (20 quarters as of the end of the third quarter of fiscal 2016). The Company recognized approximately $112,000 and $337,000 in gift card breakage revenue for the 13 and 39 weeks ended October 2, 2016, respectively, compared to approximately $112,000 and $335,000 in gift card breakage revenue for the 13 and 39 weeks ended September 27, 2015, respectively. The Company had outstanding gift card liabilities of $3.9 million and $4.9 million as of October 2, 2016 and January 3, 2016, respectively, which are included in accrued expenses. The Company records sales tax collected from its customers on a net basis, and therefore excludes it from revenue as defined in Accounting Standards Codification (“ASC”) 605, Revenue Recognition.
Share-Based Compensation	Share-Based Compensation The Company accounts for share-based compensation in accordance with ASC 718, Compensation—Stock Compensation. The Company recognizes compensation expense on a straight-line basis over the requisite service period using the fair-value method for share option awards, nonvested share awards and nonvested share unit awards granted with service-only conditions. See Note 10 to the Interim Financial Statements for a further discussion on share-based compensation.
Valuation of Merchandise Inventories, Net	Valuation of Merchandise Inventories, Net The Company’s merchandise inventories are made up of finished goods and are valued at the lower of cost or net realizable value using the weighted-average cost method that approximates the first-in, first-out (“FIFO”) method. Average cost includes the direct purchase price of merchandise inventory, net of certain vendor allowances and cash discounts, in-bound freight-related expense and allocated overhead expense associated with the Company’s distribution center. Management regularly reviews inventories and records valuation reserves for damaged and defective merchandise, merchandise items with slow-moving or obsolescence exposure and merchandise that has a carrying value that exceeds net realizable value. Because of its merchandise mix, the Company has not historically experienced significant occurrences of obsolescence. Inventory shrinkage is accrued as a percentage of merchandise sales based on historical inventory shrinkage trends. The Company performs physical inventories of its stores at least once per year and cycle counts inventories at its distribution center throughout the year. The reserve for inventory shrinkage primarily represents an estimate for inventory shrinkage for each store since the last physical inventory date through the reporting date. These reserves are estimates, which could vary significantly, either favorably or unfavorably, from actual results if future economic conditions, consumer demand and competitive environments differ from expectations.
Valuation of Long-Lived Assets	Valuation of Long-Lived Assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Long-lived assets are reviewed for recoverability at the lowest level in which there are identifiable cash flows (“asset group”), usually at the store level. Each store typically requires net investments of approximately $0.5 million in long-lived assets to be held and used, subject to recoverability testing. The carrying amount of an asset group is not considered recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the asset group. If the asset group is determined not to be recoverable, then an impairment charge will be recognized in the amount by which the carrying amount of the asset group exceeds its fair value, determined using discounted cash flow valuation techniques, as defined in ASC 360, Property, Plant, and Equipment. The Company determines the sum of the undiscounted cash flows expected to result from the asset group by projecting future revenue, gross margin and operating expense for each store under evaluation for impairment. The estimates of future cash flows involve management judgment and are based upon assumptions about expected future operating performance. Assumptions used in these forecasts are consistent with internal planning, and include assumptions about sales growth rates, gross margins and operating expense in relation to the current economic environment and future expectations, competitive factors in various markets and inflation. The actual cash flows could differ from management’s estimates due to changes in business conditions, operating performance and economic conditions. The Company recognized no impairment charges in the first 39 weeks of fiscal 2015 or 2016.
Leases and Deferred Rent	Leases and Deferred Rent The Company accounts for its leases under the provisions of ASC 840, Leases. The Company evaluates and classifies its leases as either operating or capital leases for financial reporting purposes. Operating lease commitments consist principally of leases for the Company’s retail store facilities, distribution center, corporate office, information technology hardware and distribution center delivery tractors. Capital lease obligations consist principally of leases for some of the Company’s information technology hardware. Certain of the leases for the Company’s retail store facilities provide for payments based on future sales volumes at the leased location, which are not measurable at the inception of the lease. These contingent rents are expensed as they accrue. Deferred rent represents the difference between rent paid and the amounts expensed for operating leases. Certain leases have scheduled rent increases, and certain leases include an initial period of free or reduced rent as an inducement to enter into the lease agreement (“rent holidays”). The Company recognizes rent expense for rent increases and rent holidays on a straight-line basis over the term of the underlying leases, without regard to when rent payments are made. The calculation of straight-line rent is based on the “reasonably assured” lease term as defined in ASC 840 and may exceed the initial non-cancelable lease term. Landlord allowances for tenant improvements, or lease incentives, are recorded as deferred rent and amortized on a straight-line basis over the “reasonably assured” lease term as a component of rent expense.