Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited interim condensed consolidated financial statements include the accounts of BlueLinx Holdings Inc. and its wholly owned subsidiaries (the “Company”). The Company is composed of a single reportable segment for financial reporting purposes. We derived the condensed consolidated balance sheet as of December 31, 2022 from the audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the “Fiscal 2022 Form 10-K”), as filed with the Securities and Exchange Commission (“SEC”) on February 21, 2023. In the opinion of our management, the condensed consolidated financial statements reflect all adjustments, which are of a normal recurring nature, necessary for a fair presentation of our statements of operations and comprehensive income for the three and nine months ended September 30, 2023 and October 1, 2022, our balance sheets as of September 30, 2023 and December 31, 2022, our statements of stockholders’ equity for the nine months ended September 30, 2023 and October 1, 2022, and our statements of cash flows for the nine months ended September 30, 2023 and October 1, 2022. We have condensed or omitted certain notes and other information from the interim condensed consolidated financial statements presented in this report. Therefore, these interim condensed consolidated financial statements should be read in conjunction with the Fiscal 2022 Form 10-K. The results for the three and nine months ended September 30, 2023 are not necessarily indicative of results that may be expected for the full fiscal year ending December 30, 2023, or any other interim period. We operate on a 5-4-4 fiscal calendar. Our fiscal year ends on the Saturday closest to December 31 and may comprise 53 weeks in certain years. Our 2023 fiscal year contains 52 weeks and ends on December 30, 2023. Fiscal 2022 contained 52 weeks and ended on December 31, 2022. Our financial statements are prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”), which requires us to make estimates based on assumptions about current and, for some estimates, future economic and market conditions, which affect reported amounts and related disclosures in our financial statements. Although our current estimates contemplate current and expected future conditions, as applicable, it is reasonably possible that actual conditions could differ from our expectations, which could materially affect our results of operations and financial position. Reclassification of Prior Period Presentation For the nine months ended October 1, 2022, we have reclassified certain items within the presentation of our statement of cash flows to align with our statement of cash flows presentation for the nine months ended September 30, 2023. Our reclassifications are limited to the operating activities section and include presenting pension contributions, which were previously presented within the change of other assets and liabilities, as an individual item within changes in operating assets and liabilities. These reclassifications, we believe, provide an enhanced level of transparency with regards to the presentation of our statement of cash flows. Recently Adopted Accounting Standards Credit Impairment Losses. In June 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, “Financial Instruments - Credit Losses (Topic 326).” This ASU sets forth a current expected credit loss (“CECL”) model which requires the measurement of all expected credit losses for financial instruments or other assets (e.g., trade receivables), held at the reporting date based on historical experience, current conditions, and reasonable supportable forecasts. This replaces the former incurred loss model applicable to the measurement of credit losses on financial assets measured at amortized cost, and applies to some off-balance sheet credit exposures. The standard also requires enhanced disclosures to help financial statement users better understand significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an entity's portfolio. The Company adopted this standard on a modified retrospective basis in the first quarter of 2022 and the implementation did not have a material impact to the Company’s condensed consolidated financial statements. Reference Rate Reform. In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” The standard provides temporary guidance to ease the potential burden in accounting for reference rate reform primarily resulting from the discontinuation of the publication of certain tenors of the London Inter-bank Offered Rate (“LIBOR”) on December 31, 2021, with complete elimination of the publication of the LIBOR by June 30, 2023. The amendments in this ASU are elective and apply to all entities that have contracts referencing the LIBOR. The Company’s revolving credit agreement, as further discussed in Note 6, Long-Term Debt, to these condensed consolidated financial statements, was amended on June 27, 2023, to replace references to LIBOR with Secured Overnight Financing Rate (“SOFR”) for determining interest payable on current and future borrowings. The guidance in this ASU provides a practical expedient which simplifies accounting analyses under current U.S. GAAP for contract modifications if the change is directly related to a change from the LIBOR to a new interest rate index. The Company adopted this standard prospectively in the first quarter of 2022. The implementation did not have a material impact on the Company’s condensed consolidated financial statements or to any key terms of our revolving credit agreement other than the discontinuation of LIBOR.