Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Nov. 03, 2018
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation. The accompanying unaudited interim condensed consolidated financial statements have been prepared from the records of Ross Stores, Inc. and subsidiaries (the “Company”) without audit and, in the opinion of management, include all adjustments (consisting of only normal, recurring adjustments) necessary to present fairly the Company’s financial position as of November 3, 2018 and October 28, 2017, the results of operations and comprehensive income for the three and nine month periods ended November 3, 2018 and October 28, 2017, and cash flows for the nine month periods ended November 3, 2018 and October 28, 2017. The Condensed Consolidated Balance Sheet as of February 3, 2018, presented herein, has been derived from the Company’s audited consolidated financial statements for the fiscal year then ended. Certain information and disclosures normally included in the notes to annual consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted for purposes of these interim condensed consolidated financial statements. The interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements, including notes thereto, contained in the Company’s Annual Report on Form 10-K for the year ended February 3, 2018. The results of operations and comprehensive income for the three and nine month periods ended November 3, 2018 and October 28, 2017 presented herein are not necessarily indicative of the results to be expected for the full fiscal year. Significant accounting policies. Except for the updates to accounting policies for revenue recognition and allowance for sales returns as a result of adopting ASC 606 described below, there have been no significant changes to the accounting policies followed by the Company as described in Note A to the audited consolidated financial statements for the fiscal year ended February 3, 2018.
Revenue recognition and allowance for sales returns	Allowance for sales returns. As a result of the adoption of ASC 606, the Company recognizes allowances for estimated sales returns on a gross basis. This results in (i) an asset recorded for the expected recovery of merchandise inventory and a liability recorded for the refund due to the customer and (ii) a change in sales and related cost of goods sold based on the required reserve for estimated returns. Prior to the adoption of ASC 606, the Company recognized allowances for sales returns on a net basis. Revenue recognition. The Company recognizes revenue at the point of sale, net of sales taxes collected and an allowance for estimated future returns. Sales taxes collected that are outstanding and the allowance for estimated future returns are included in Accrued expenses and other in the Condensed Consolidated Balance Sheets. Sales of stored value cards are deferred until they are redeemed for the purchase of Company merchandise. The Company’s stored value cards do not have expiration dates. Based upon historical redemption rates, a small percentage of stored value cards will never be redeemed, which represents breakage. As a result of adopting ASC 606, breakage is estimated and recognized as revenue based upon the historical pattern of customer redemptions. In prior periods, breakage was recorded as a reduction of operating expense when customer redemption was considered remote. Breakage was not material to the condensed consolidated financial statements for the three and nine month periods ended November 3, 2018 and October 28, 2017.
Cash, restricted cash, and restricted investments	Cash, restricted cash, and restricted investments. Restricted cash, cash equivalents, and investments serve as collateral for certain insurance obligations of the Company. These restricted funds are invested in bank deposits, money market mutual funds, U.S. Government and agency securities, and corporate securities and cannot be withdrawn from the Company’s account without the prior written consent of the secured parties. The classification between current and long-term is based on the timing of expected payments of the insurance obligations.
Property and equipment	Property and equipment. As of November 3, 2018 and October 28, 2017, the Company had $13.0 million and $6.4 million, respectively, of property and equipment purchased but not yet paid. These purchases are included in Property and Equipment, Accounts payable, and Accrued expenses and other in the accompanying Condensed Consolidated Balance Sheets.
Recently issued and adopted accounting standards	Recently adopted accounting standards. In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-09, Revenue from Contracts with Customers (Accounting Standards Codification "ASC" 606) which, along with subsequent amendments, supersedes the revenue recognition requirements in “Revenue Recognition (ASC 605).” This guidance provides a five-step analysis of transactions to determine when and how revenue is recognized and requires entities to recognize revenue when the customer obtains control of promised goods or services in an amount that reflects the consideration the entity expects to receive in exchange for those goods or services. The Company adopted ASC 606 as of February 4, 2018, using the modified retrospective method. Results for reporting periods beginning on or after February 4, 2018 are presented under ASC 606, while prior period amounts were not adjusted and continue to be reported in accordance with ASC 605. Upon adoption of ASC 606, the Company recorded a cumulative-effect adjustment to increase beginning retained earnings by $20 million as of February 4, 2018, primarily due to the change in the timing of the recognition of stored value card breakage. The impact of applying ASC 606 was not material to the Company's condensed consolidated financial statements for the three and nine month periods ended November 3, 2018. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash. ASU 2016-18 requires restricted cash and restricted cash equivalents be included with cash and cash equivalents when reconciling the total beginning and ending amounts on the statement of cash flows. The standard also requires companies who report cash and restricted cash separately on the balance sheet to reconcile those amounts to the statement of cash flows. The Company adopted ASU 2016-18 as of February 4, 2018, using the retrospective method. Recently issued accounting standards. The Company considers the applicability and impact of all ASUs issued by the FASB. ASUs not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on the Company's condensed consolidated financial results. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The ASU requires balance sheet recognition for all leases with lease terms greater than one year including a lease liability, which is a lessee's obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. ASU 2016-02 is effective for the Company’s annual and interim reporting periods beginning in fiscal 2019. In July 2018, the FASB issued ASU 2018-11, “Leases (Topic 842): Targeted Improvements.” This update provides an additional (and optional) transition method to adopt the new leases standard, which allows entities to initially apply the new standard at the effective date with a cumulative-effect adjustment to the opening balance of retained earnings and does not require restatement of prior periods. The Company plans to adopt the new leases standard using the optional transition method. In addition, the Company does not plan to elect the transitional package of practical expedients or the use of hindsight upon adoption. The Company is finalizing the expected effect adoption of this new guidance will have on its consolidated financial statements. Due to the substantial number of leases that it has, the Company believes this ASU will increase assets and liabilities by a material amount on its consolidated balance sheet. The Company’s current undiscounted minimum commitments under noncancelable operating leases is approximately $3.9 billion. The Company does not believe adoption of this ASU will have a significant impact to its consolidated statements of earnings, stockholders’ equity, and cash flows.
Fair value measurement	Fair Value Measurements The carrying value of cash and cash equivalents, short- and long-term investments, restricted cash and cash equivalents, restricted investments, accounts receivable, other long-term assets, accounts payable, and other long-term liabilities approximates their estimated fair value. Accounting standards pertaining to fair value measurements establish a three-tier fair value hierarchy which prioritizes the inputs used in measuring fair value. The inputs used to measure fair value include: Level 1, observable inputs such as quoted prices in active markets; Level 2, inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, unobservable inputs in which little or no market data exists. This fair value hierarchy requires the Company to develop its own assumptions and maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Corporate, U.S. government and agency, and mortgage-backed securities are classified within Level 1 or Level 2 because these securities are valued using quoted market prices or alternative pricing sources and models utilizing market observable inputs.
Earnings per share	Earnings Per Share The Company computes and reports both basic earnings per share ("EPS") and diluted EPS. Basic EPS is computed by dividing net earnings by the weighted average number of common shares outstanding for the period. Diluted EPS is computed by dividing net earnings by the sum of the weighted average number of common shares and dilutive common stock equivalents outstanding during the period. Diluted EPS reflects the total potential dilution that could occur from outstanding equity plan awards, including unexercised stock options, and unvested shares of both performance and non-performance based awards of restricted stock.