Nature of Operations and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations The accompanying Unaudited Condensed Consolidated Financial Statements include the accounts of NACCO Industries, Inc. (the “parent company” or “NACCO”) and its wholly owned subsidiaries (collectively, “NACCO Industries, Inc. and Subsidiaries” or the “Company”). Intercompany accounts and transactions are eliminated in consolidation. The Company's primary operating subsidiary operates in the mining industry. The North American Coal Corporation and its affiliated companies (collectively, “NACoal”) mine coal primarily for use in power generation and provide value-added services for natural resource companies. On September 29, 2017, the Company spun-off Hamilton Beach Brands Holding Company ("HBBHC"), a former wholly owned subsidiary. HBBHC is an operating holding company for two separate businesses: consumer, commercial and specialty small appliances (Hamilton Beach Brands, Inc. or "HBB") and specialty retail (The Kitchen Collection, LLC or "KC"). The financial position, results of operations and cash flows of HBBHC are reflected as discontinued operations for all periods presented through the date of the spin-off. See Note 10 to the Unaudited Condensed Consolidated Financial Statements for further details regarding the spin-off. NACoal has the following operating coal mining subsidiaries: Bisti Fuels Company, LLC ("Bisti"), Caddo Creek Resources Company, LLC (“Caddo Creek”), Camino Real Fuels, LLC (“Camino Real”), The Coteau Properties Company (“Coteau”), Coyote Creek Mining Company, LLC (“Coyote Creek”), Demery Resources Company, LLC (“Demery”), The Falkirk Mining Company (“Falkirk”), Liberty Fuels Company, LLC (“Liberty”), Mississippi Lignite Mining Company (“MLMC”) and The Sabine Mining Company (“Sabine”). All of the operating coal mining subsidiaries other than MLMC are unconsolidated (collectively the "Unconsolidated Mines"). The Unconsolidated Mines were formed to develop, construct and/or operate surface coal mines under long-term contracts and are capitalized primarily with debt financing provided by or supported by their respective customers, and without recourse to NACCO and NACoal. The contracts with the customers of the Unconsolidated Mines provide for reimbursement to the company at a price based on actual costs plus an agreed upon pre-tax profit per ton of coal sold or actual costs plus an agreed upon fee per btu of heating value delivered. The fees earned at each mine adjust over time in line with various indices which reflect general U.S. inflation rates. Although NACoal owns 100% of the equity and manages the daily operations of the Unconsolidated Mines, the Company has determined that the equity capital provided by NACoal is not sufficient to adequately finance the ongoing activities or absorb any expected losses without additional support from the customers. The customers have a controlling financial interest and have the power to direct the activities that most significantly affect the economic performance of the entities. As a result, NACoal is not the primary beneficiary and therefore does not consolidate these entities' financial position or results of operations. The income taxes resulting from operations of the Unconsolidated Mines are solely the responsibility of the Company. The pre-tax income from the Unconsolidated Mines is reported on the line “Earnings of unconsolidated mines” in the Consolidated Statements of Operations, with related taxes included in the provision for income taxes. The Company has included the pre-tax earnings of the Unconsolidated Mines above operating profit as they are an integral component of the Company's business and operating results. MLMC is a consolidated entity because NACoal pays all operating costs and provides the capital for the mine. MLMC sells coal to its customer at a contractually agreed upon price which adjusts monthly, primarily based on changes in the level of established indices which reflect general U.S. inflation rates. Centennial Natural Resources, LLC ("Centennial"), which ceased coal production in the fourth quarter of 2015, is also a consolidated entity. NACoal provides value-added mining services for independently owned limerock quarries through its North American Mining ("NAM") division. NAM is reimbursed by its customers based on actual costs plus a management fee. The financial results for NAM are included in consolidated mining operations or unconsolidated mining operations based on each NAM entity's structure. NACoal also provides coal handling, processing and drying services for a number of customers. For example, NoDak Energy Services, LLC ("NoDak") operates and maintains a coal processing facility for a customer's power plant. The pre-tax income from NoDak is reported on the line "Income from other unconsolidated affiliates" in the "Other (income) expense" section of the Consolidated Statements of Operations, with the related income taxes included in the provision for income taxes. North American Coal Royalty Company, a consolidated entity, provides surface and mineral acquisition and lease maintenance services related to the Company's operations. All of the unconsolidated subsidiaries are accounted for under the equity method.
Basis of Presentation	Basis of Presentation These financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation of the financial position of the Company at September 30, 2017 and the results of its operations, comprehensive income (loss), cash flows and changes in equity for the nine months ended September 30, 2017 and 2016 have been included. These Unaudited Condensed Consolidated Financial Statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016. The balance sheet at December 31, 2016 has been derived from the audited financial statements at that date but does not include all of the information or notes required by U.S. GAAP for complete financial statements.
Accounting Standards Not Yet Adopted	Accounting Standards Not Yet Adopted In May 2014, the FASB codified ASC 606, "Revenue Recognition - Revenue from Contracts with Customers," which supersedes most current revenue recognition guidance, including industry-specific guidance, and requires an entity to recognize revenue in an amount that reflects the consideration to which the entity expects to be entitled in exchange for transferring goods or services to customers and provide additional disclosures. As amended, the effective date for public entities is annual reporting periods beginning after December 15, 2017 and interim periods therein. The Company anticipates adopting the new revenue guidance effective January 1, 2018 using the modified retrospective method with the cumulative effect of initially applying the standard recognized as an adjustment to equity. The Company has developed a project plan with respect to its implementation of this standard, including identification of revenue streams and review of contracts and procedures currently in place. The Company is in the process of completing its review of customer contracts at its NACoal subsidiary, including the contracts for the Company’s Unconsolidated Mines, and finalizing its conclusions on a variety of specific contractual terms. These include identification of additional performance obligations, specifically during the pre- and post-coal production periods, variable compensation considerations and the timing of recognition of royalty revenue. While the revenue of the Unconsolidated Mines is not consolidated within the Company’s financial statements, any change in the amount or timing of revenue recognition at the Unconsolidated Mines could have an impact on the company’s recognition of earnings from the unconsolidated mines. The Company is also in the process of identifying and implementing any necessary changes to processes and controls to meet the standard's updated reporting and disclosure requirements. The Company continues to assess the potential impact of the standard and has not yet reached a conclusion as to how the adoption of the standard will impact the Company's financial position, results of operations or cash flows. The adoption of this guidance will result in increased disclosures to help users of financial statements understand the nature, amount and timing of revenue and cash flows arising from contracts. In January 2016, the FASB issued ASU No. 2016-01, "Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities," which modifies how entities measure equity investments and present changes in the fair value of financial liabilities; simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; changes presentation and disclosure requirements; and clarifies that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. ASU 2016-01 is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company is evaluating the impact that this new guidance will have on the Company’s financial position, results of operations, cash flows and related disclosures. In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)," which requires an entity to recognize assets and liabilities for the rights and obligations created by leased assets. ASU 2016-02 is effective for interim and annual periods beginning after December 15, 2018, and early adoption is permitted. The Company is currently evaluating how and to what extent ASU 2016-02 will affect the Company's financial position, results of operations, cash flows and related disclosures.