Business Segments (Balance Sheets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total assets	$ 376,991	$ 389,552
Depreciation, depletion and amortization	14,683	12,767
Capital expenditures	20,930	15,704
Operating Segments | NACoal
Segment Reporting Information [Line Items]
Total assets	274,800	277,538
Depreciation, depletion and amortization	14,596	12,444
Capital expenditures	20,799	15,692
NACCO and Other | NACCO and Other
Segment Reporting Information [Line Items]
Total assets	120,954	135,434
Depreciation, depletion and amortization	87	323
Capital expenditures	131	12
Eliminations
Segment Reporting Information [Line Items]
Total assets	$ (18,763)	$ (23,420)