Long-Term Debt And Other Long-Term Liabilities (Other Long-Term Liabilities) (Details) - USD ($) $ in Thousands		Sep. 30, 2020	Sep. 01, 2020	Aug. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Debt Disclosure [Abstract]
Asset retirement obligation (ARO) liability		$ 24,922	$ 24,591	$ 38,984	$ 66,627	$ 64,072	$ 64,208
Workers' compensation		11,664			11,510
Contract liability		4,899			7,061
Separation benefit plans	[1]	4,536			10,122
Finance lease obligations		4,272			7,379
Gas balancing liability		3,824			3,838
Deferred compensation plan		0			6,180
Other long-term liability		1,997			0
Other liabilities		56,114			112,717
Current portion of other long-term liabilities		12,324			17,376
Total other long-term liabilities		$ 43,790			$ 95,341

[1] As of the Effective Date, the Board adopted (i) the Amended and Restated Separation Benefit Plan of Unit Corporation and Participating Subsidiaries (Amended Separation Benefit Plan), (ii) the Amended and Restated Special Separation Benefit Plan of Unit Corporation and Participating Subsidiaries (Amended Special Separation Benefit Plan) and (iii) the Separation Benefit Plan of Unit Corporation and Participating Subsidiaries (New Separation Benefit Plan). In accordance with the Plan, the Amended Separation Benefit Plan and the Amended Special Separation Benefit Plan allow former employees or retained employees with vested severance benefits under either plan to receive certain cash payments in full satisfaction for their allowed separation claim under the Chapter 11 Cases. In accordance with the Plan, the New Separation Benefit Plan is a comprehensive severance plan for retained employees, including retained employees whose severance did not already vest under the Amended Separation Benefit Plan or the Amended Special Separation Benefit Plan. The New Separation Benefit Plan provides that eligible employees will be entitled to two weeks of severance pay per year of service, with a minimum of four weeks and a maximum of 13 weeks of severance pay.