Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended	8 Months Ended	9 Months Ended
	Sep. 30, 2020	Aug. 31, 2020	Sep. 30, 2019	Aug. 31, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Earnings (loss) of basic income (loss) attributable to Unit Corporation per common share	$ (8,968)	$ 55,131	$ (206,886)	$ (931,012)	$ (218,899)
Income of effect of dilutive stock options and restricted stock			0		0
Earnings (loss) of diluted income (loss) attributable to Unit Corporation per common share			$ (206,886)		$ (218,899)
Weighted shares of basic earnings (loss) attributable to Unit Corporation per common share	12,000	53,519	52,950	53,368	52,814
Weighted shares of effect of dilutive stock options and restricted stock			0		0
Weighted shares of diluted earnings (loss) attributable to Unit Corporation per common share			52,950		52,814
Per-Share amount of basic earnings (loss) attributable to Unit Corporation per common share	$ (0.75)	$ 1.03	$ (3.91)	$ (17.45)	$ (4.14)
Per-Share amount of effect of dilutive stock options and restricted stock			0		0
Per-Share amount of diluted earnings (loss) attributable to Unit Corporation per common share		$ 1.03	$ (3.91)	$ (17.45)	$ (4.14)