Accounting Policies, by Policy (Policies)	12 Months Ended
Dec. 31, 2014
Accounting Policies [Abstract]
Nature of Business [Policy Text Block]	Nature of Business The Company is a leading U.S. metals service center specializing in the processing and distribution of large volumes of carbon, coated, aluminum and stainless steel, flat-rolled coil, sheet and plate products and tubular and pipe products from facilities throughout the United States. The Company operates in two reportable segments; flat products and tubular and pipe products. In recent years the Company has increased its participation in the stainless and aluminum markets, which the Company refers to as specialty metals. As a result, based on how the chief operating decision maker, or CODM, is expected to make decisions, assess performance and allocate resources in the future, the Company expects to disclose three reportable segments beginning in the first quarter of 2015. The segments will be flat products, tubular and pipe products, and specialty metals. Through its flat products segment, the Company sells and distributes large volumes of processed carbon, coated, aluminum and stainless flat-rolled sheet, coil and plate products. Through its tubular and pipe products segment, the Company distributes metals tubing, pipe, bar, valve and fittings and the fabrication of pressure parts supplied to various industrial markets.
Consolidation, Policy [Policy Text Block]	Principles of Consolidation and Basis of presentation The accompanying consolidated financial statements include the accounts of Olympic Steel, Inc. and its wholly-owned subsidiaries (collectively, the Company or Olympic), after elimination of intercompany accounts and transactions.
Use of Estimates, Policy [Policy Text Block]	Accounting Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Concentration Risks The Company is a major customer of flat-rolled coil and plate and tubular and pipe steel for many of its principal suppliers, but is not dependent on any one supplier. The Company purchased approximately 43%, 42%, and 44% of its total steel requirements from its three largest suppliers in 2014, 2013 and 2012, respectively. The Company has a diversified customer and geographic base, which reduces the inherent risk and cyclicality of its business. The concentration of net sales to the Company’s top 20 customers approximated 29%, 30% and 31% of consolidated net sales in 2014, 2013 and 2012, respectively. In addition, the Company’s largest customer accounted for approximately 6%, 5% and 4% of consolidated net sales in 2014, 2013 and 2012, respectively. Sales to industrial machinery and equipment manufacturers and their fabricators accounted for 51%, 50% and 50% of consolidated net sales in 2014, 2013 and 2012, respectively.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents Cash equivalents consist of short-term highly liquid investments, with a three month or less maturity, which are readily convertible into cash.
Fair Value Measurement, Policy [Policy Text Block]	Fair Market Value Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability in the principal or most advantageous market for the liability in an orderly transaction between market participants on the measurement date. Valuation techniques must maximize the use of observable inputs and minimize the use of unobservable inputs. To measure fair value, the Company applies a fair value hierarchy that is based on three levels of inputs, of which the first two are considered observable and the last unobservable, as follows: Level 1 – Quoted prices in active markets for identical assets or liabilities. Level 2 – Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Financial instruments, such as cash and cash equivalents, accounts receivable, accounts payable and the credit facility revolver, are stated at their carrying value, which is a reasonable estimate of fair value. The fair value of marketable securities is based on quoted market prices.
Trade and Other Accounts Receivable, Policy [Policy Text Block]	Accounts Receivable The Company’s allowance for doubtful accounts is maintained at a level considered appropriate based on historical experience and specific customer collection issues that the Company has identified. Estimations are based upon a calculated percentage of accounts receivable, which remains fairly level from year to year, and judgments about the probable effects of economic conditions on certain customers, which can fluctuate significantly from year to year. The Company cannot guarantee that the rate of future credit losses will be similar to past experience.
Inventory, Policy [Policy Text Block]	Inventories Inventories are stated at the lower of cost or market and include the costs of purchased metals, inbound freight, external processing and applicable labor and overhead costs. Costs of our flat products segment’s inventories, including flat-rolled sheet, coil and plate products are determined using the specific identification method. Certain of the Company’s tubular and pipe products inventory is stated under the last-in, first-out (LIFO) method. At December 31, 2014 and December 31, 2013, approximately $46.6 million, or 15.0% of consolidated inventory, and $43.9 million, or 15.3% of consolidated inventory, respectively, was reported under the LIFO method of accounting. The cost of the remainder of tubular and pipe product segment’s inventory is determined using a weighted average rolling first-in, first-out (FIFO) method. On the Consolidated Statements of Comprehensive Income, “Cost of materials sold (exclusive of items shown separately below)” consists of the cost of purchased metals, inbound and internal transfer freight, external processing costs, and LIFO income or expense.
Property, Plant and Equipment, Policy [Policy Text Block]	Property and Equipment, and Depreciation Property and equipment are stated at cost. Depreciation is provided using the straight-line method over the estimated useful lives of the assets ranging from two to 30 years. The Company capitalizes the costs of obtaining or developing internal-use software, including directly related payroll costs. The Company amortizes those costs over five years, beginning when the software is ready for its intended use.
Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]	Goodwill and Other Intangible Assets Goodwill represents the excess of the purchase price paid over the fair value of the net assets acquired. The Company performs an annual impairment test of goodwill for our Integrity Stainless and tubular and pipe products segment and indefinite-lived intangible assets for the tubular and pipe products segment in the fourth quarter, or more frequently if changes in circumstances or the occurrence of events indicate potential impairment. Events or changes in circumstances that could trigger an impairment review include significant nonperformance relative to the expected historical or projected future operating results, significant changes in the manner of the use of the acquired assets or the strategy for the overall business or significant negative industry or economic trends. Management uses judgment to determine whether to use a qualitative analysis or a quantitative fair value measurement for each of the Company’s reporting units that carry goodwill. If a quantitative fair value measurement is used, the fair value of each indefinite-lived intangible asset is compared to its carrying value and an impairment charge is recorded if the carrying value exceeds the fair value. Goodwill is tested by comparing the fair value of each reporting unit with its carrying value. If the carrying value of the reporting unit exceeds its fair value, the implied value of goodwill is compared to its carrying value and impairment is recognized to the extent that the carrying value exceeds the implied fair value. The Company estimates the fair value of goodwill and other indefinite-lived intangible assets using a discounted cash flow methodology, an income approach, and a publicly traded companies guideline method, a market approach. Management’s assumptions used for the calculations are based on historical results, projected financial information and recent economic events. Actual results could differ from these estimates under different assumptions or conditions which could adversely affect the reported value of goodwill. During the fourth quarter of 2014, the Company engaged an independent third party valuation expert to assist with the completion of the annual goodwill impairment testing pursuant ASC Topic 350-20-35, “Goodwill – Subsequent measurement.” Due to challenging market conditions, the Company’s recent financial performance and the decrease of the Company’s market capitalization, the Company decided to perform the two-step quantitative impairment test by comparing the fair value of the Integrity Stainless and tubular and pipe products segment with its carrying value. The first step of the goodwill impairment test showed that the fair value of the Integrity Stainless operations was in excess of its carrying value and no goodwill impairment was identified. For the Company’s tubular and pipe products segment, it was determined that the carrying value of the operations was in excess of the fair value and a potential goodwill impairment was identified. Based on the second step of the impairment test, the Company concluded that the implied fair value of goodwill for the tubular and pipe products segment was less than its carrying value and a goodwill impairment of $23.8 million was identified and recognized.
Income Tax, Policy [Policy Text Block]	Income Taxes The Company, on its consolidated balance sheets, records as an offset to the estimated effect of temporary differences between the tax basis of assets and liabilities and the reported amounts in its consolidated balance sheets, the tax effect of operating loss and tax credit carryforwards. If the Company determines that it will not be able to fully realize a deferred tax asset, it will record a valuation allowance to reduce such deferred tax asset to its realizable value. The Company recognizes interest accrued related to unrecognized tax benefits in income tax expense. Penalties, if incurred, would be recognized as a component of administrative and general expense.
Revenue Recognition, Policy [Policy Text Block]	Revenue Recognition For both direct and toll shipments, revenue is recognized when title and risk of loss is transferred, which generally occurs upon delivery to our customers. Given the proximity of the Company’s customers to its facilities, substantially all of the Company’s sales are shipped and received within one day. Sales returns and allowances are treated as reductions to sales and are provided for based on historical experience and current estimates and are immaterial to the consolidated financial statements. The engineered products produced by Chicago Tube and Iron Company (CTI) typically take several months to produce due to their size and complexity. Substantially all projects are completed within six months. The Company may request advance payments from customers during the production of these products. These payments are included in current short-term liabilities on the Company’s Consolidated Balance Sheet. Due to their short-term nature, the Company uses the units of delivery method to account for these contracts. Revenue for the contracts is recognized when the product is shipped and title of the product transfers to the customers. Revenues for these engineered products accounted for approximately 1.7%, 1.9% and 1.3% of our net sales during 2014, 2013 and 2012, respectively.
Shipping and Handling Cost, Policy [Policy Text Block]	Shipping and Handling Fees and Costs Amounts charged to customers for shipping and other transportation services are included in net sales. The distribution expense line on the accompanying Consolidated Statements of Comprehensive Income is entirely comprised of all shipping and other transportation costs incurred by the Company in shipping goods to its customers.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	Recoverability of Long-lived Assets The Company evaluates the recoverability of long-lived assets and the related estimated remaining lives whenever events or changes in circumstances indicate that the carrying value may not be recoverable. Events or changes in circumstances that could trigger an impairment review include significant underperformance relative to the expected historical or projected future operating results, significant changes in the manner of the use of the acquired assets or the strategy for the overall business or significant negative industry or economic trends. The Company records an impairment or change in useful life whenever events or changes in circumstances indicate that the carrying amount may not be recoverable or the useful life has changed. Due to the impairment of the tubular and pipe products segment’s goodwill, a triggering event occurred for the Company’s long-lived assets. We performed an undiscounted cash flow analysis which indicated that there were no indicators of impairment of the long-lived assets of the Company.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	Stock-Based Compensation The Company records compensation expense for stock options issued to employees and directors. The Company has elected to use the modified prospective transition method where compensation expense is recorded prospectively. For additional information, see Note 11, Equity Plans.
New Accounting Pronouncements, Policy [Policy Text Block]	Impact of Recently Issued Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (FASB) issued ASU No. 2014-09, “Revenue from Contracts with Customers.” This ASU is a joint project initiated by the Financial Accounting Standards Board and the International Accounting Standards Board to clarify the principles for recognizing revenue and to develop a common revenue standard for U.S. generally accepted accounting principles and International Financial Reporting Standards that will remove inconsistencies and weaknesses in revenue requirements; provide a more robust framework for addressing revenue issues; improve comparability of revenue recognition practices across entities, industries, jurisdictions and capital markets; provide more useful information to users of financial statements through improved disclosure requirements; and simplify the preparation of financial statements by reducing the number of requirements to which an entity must refer. The guidance is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. The Company is in the process of determining the method of adoption and assessing the impact of this ASU on its consolidated financial statements. In August 2014, the FASB issued ASU No. 2014-15, “Presentation of Financial Statements – Going Concern”. This ASU contains new guidance on management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. Management must evaluate whether it is probable that known conditions or events, considered in the aggregate, would raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued. If such conditions or events are identified, the standard requires management's mitigation plans to alleviate the doubt or a statement of the substantial doubt about the entity’s ability to continue as a going concern to be disclosed in the financial statements. This ASU is effective for fiscal years and interim periods beginning after December 15, 2016, with early adoption permitted. The adoption of this ASU is not expected to impact the Company’s consolidated financial statements.

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Disclosure of accounting policy for cash and cash equivalents, including the policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value.