XML 12 R1.htm IDEA: XBRL DOCUMENT v3.7.0.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2017
Apr. 28, 2017
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, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q1  
Amendment Flag false  
Shares Outstanding Class A    
Entity Information [Line Items]    
Shares Outstanding (in shares)   5,263,374
Shares Outstanding Class B    
Entity Information [Line Items]    
Shares Outstanding (in shares)   1,570,448