Business Segments (Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Total assets	$ 770,520us-gaap_Assets	$ 809,956us-gaap_Assets	$ 776,306us-gaap_Assets
Depreciation, depletion and amortization	28,070	24,572	17,992
Capital expenditures, excluding acquisitions of business	57,500	57,449	44,682
NACoal
Segment Reporting Information [Line Items]
Total assets	389,964	419,786	368,652
Depreciation, depletion and amortization	22,003	16,601	10,849
Capital expenditures, excluding acquisitions of business	51,228	52,748	37,125
HBB
Segment Reporting Information [Line Items]
Total assets	270,265	228,891	215,503
Depreciation, depletion and amortization	2,693	3,475	3,113
Capital expenditures, excluding acquisitions of business	4,516	2,313	3,223
KC
Segment Reporting Information [Line Items]
Total assets	56,260	70,014	83,977
Depreciation, depletion and amortization	3,048	4,162	3,611
Capital expenditures, excluding acquisitions of business	1,193	2,150	3,872
NACCO and Other
Segment Reporting Information [Line Items]
Total assets	96,918	131,085	154,605
Depreciation, depletion and amortization	326	334	419
Capital expenditures, excluding acquisitions of business	563	238	462
Eliminations
Segment Reporting Information [Line Items]
Total assets	$ (42,887)	$ (39,820)	$ (46,431)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.18)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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