Note 17 - Subsequent Event	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Subsequent Events [Text Block]	(17) SUBSEQUENT EVENTS As announced in our Form 8-K filed on February 18, 2022, on February 14, 2022, Hallador Energy Company, through its subsidiary Hallador Power Company, LLC, entered into an Asset Purchase Agreement (the "Purchase Agreement") to acquire Hoosier Energy’s 1-Gigawatt Merom Generating Station, located in Sullivan County, Indiana, in return for assuming certain decommissioning costs and environmental responsibilities. The transaction, which includes a 3.5-year power purchase agreement (PPA), is scheduled to close in mid- July 2022 upon obtaining required governmental and financial approvals. On March 25, 2022, we executed an amendment to our credit agreement with PNC as discussed in Note 5 to these consolidated financial statments.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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