Note 1 - Description of Business and Basis of Presentation (Details) shares in Thousands, $ in Millions	Feb. 08, 2017 USD ($) shares
Notes Payable to Banks [Member] | Ramaco Carbon, LLC [Member]
Repayments of Related Party Debt | $	$ 10.7
IPO [Member]
Stock Issued During Period, Shares, New Issues	6,000
Proceeds from Issuance Initial Public Offering, Net of Issuance Costs | $	$ 43.7
IPO [Member] | Conversion of Series A Preferred Units Into Common Stock Upon Reorganization [Member]
Stock Issued During Period, Shares, Conversion of Units	12,760
IPO [Member] | Common Stock Sold by the Company [Member]
Stock Issued During Period, Shares, New Issues	3,800
IPO [Member] | Common Stock Sold By The Stockholders [Member]
Stock Issued During Period, Shares, New Issues	2,200