Document and Entity Information	3 Months Ended
	Mar. 31, 2012	Apr. 27, 2012 Common Class A [Member]	Apr. 27, 2012 Common Class B [Member]
Entity Information [Line Items]
Entity Registrant Name	NACCO INDUSTRIES INC
Entity Central Index Key	0000789933
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Amendment Flag	false
Shares Outstanding		6,797,404	1,590,571