| Cover Page | Nov. 03, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 3, 2021 |
| Entity Registrant Name | NACCO INDUSTRIES, INC. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-9172 |
| Entity Tax Identification Number | 34-1505819 |
| Entity Address, Address Line One | 5875 Landerbrook Drive |
| Entity Address, Address Line Two | Suite 220 |
| Entity Address, City or Town | Cleveland, |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 44124-4069 |
| City Area Code | (440) |
| Local Phone Number | 229-5151 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Common Stock, $1 par value per share |
| Trading Symbol | NC |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000789933 |
| Amendment Flag | false |
