Cover Page - shares	6 Months Ended
	Jun. 30, 2021	Jul. 30, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	1-9172
Entity Registrant Name	NACCO INDUSTRIES, INC.
Entity Incorporation, State or Country Code	DE
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
Title of 12(b) Security	Class A Common Stock, $1 par value per share
Trading Symbol	NC
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000789933
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Amendment Flag	false
Shares Outstanding Class A
Entity Information [Line Items]
Shares Outstanding (in shares)		5,595,368
Shares Outstanding Class B
Entity Information [Line Items]
Shares Outstanding (in shares)		1,566,643