Selected Quarterly Financial Information (Details) - USD ($)	1 Months Ended	2 Months Ended	3 Months Ended											4 Months Ended	8 Months Ended	12 Months Ended
	Sep. 30, 2020	Aug. 31, 2020	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2020	Aug. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Revenues	$ 32,846,000	$ 65,574,000	$ 100,682,000	$ 89,007,000	$ 122,376,000	$ 164,358,000		$ 155,439,000		$ 165,146,000		$ 189,691,000			$ 276,957,000		$ 674,634,000
Gross income (loss)	(7,373,000)	(7,637,000)	5,599,000	(171,374,000)	(764,888,000)	(393,983,000)	[1]	(242,308,000)	[1]	813,000	[1]	24,095,000	[1]
Net income (loss) attributable to Unit Corporation	$ (8,968,000)	$ 55,131,000	$ (9,172,000)	$ (215,649,000)	$ (770,494,000)	$ (334,980,000)	[2]	$ (206,886,000)		$ (8,509,000)		$ (3,504,000)		$ (18,140,000)	$ (931,012,000)		$ (553,879,000)
Net income (loss) attributable to Unit Corporation per common share:
Basic	$ (0.75)	$ 1.03	$ (0.76)	$ (4.03)	$ (14.50)	$ (6.33)		$ (3.91)		$ (0.16)		$ (0.07)		$ (1.51)	$ (17.45)		$ (10.48)
Diluted	$ (0.75)	$ 1.03	$ (0.76)	$ (4.03)	$ (14.50)	$ (6.33)		$ (3.91)		$ (0.16)		$ (0.07)		$ (1.51)	$ (17.45)		$ (10.48)
Ceiling test write-down																$ 559,400,000	$ 559,400,000
Non-cash ceiling test write-down net of tax					$ 220,800,000	$ 294,500,000		$ 127,900,000							$ 346,600,000	$ 422,400,000	422,400,000
Goodwill impairment								62,800,000
Goodwill, Impairment Loss, Net of Tax								59,800,000
Loss on abandonment of assets (Note 4)														$ 0	(18,733,000)		$ 0
Oil and Natural Gas
Net income (loss) attributable to Unit Corporation per common share:
Ceiling test write-down	$ 13,200,000	$ 16,600,000	$ 12,900,000	$ 109,300,000	267,800,000	$ 390,100,000		$ 169,300,000						$ 26,100,000	393,700,000
Loss on abandonment of assets (Note 4)															(17,600,000)
Drilling Equipment
Net income (loss) attributable to Unit Corporation per common share:
Loss on abandonment of assets (Note 4)															(1,100,000)
Drilling Equipment | Other drilling equipment
Net income (loss) attributable to Unit Corporation per common share:
Impairment of Long-Lived Assets Held-for-use															3,000,000.0
Drilling Equipment | SCR drilling rigs
Net income (loss) attributable to Unit Corporation per common share:
Impairment of Long-Lived Assets Held-for-use															$ 407,100,000
Mid-Stream
Net income (loss) attributable to Unit Corporation per common share:
Impairment of Long-Lived Assets Held-for-use					$ 64,000,000.0

[1] Gross income (loss) excludes general and administrative expense, interest expense, (gain) loss on disposition of assets, loss on abandonment of assets, gain (loss) on derivatives, reorganization items, net, income taxes, and other income (loss).

[2] During the one-month Successor Period for the third quarter of 2020, we recorded a non-cash ceiling test write-down of $13.2 million pre-tax. 4.During the fourth quarter of 2020, we recorded a non-cash ceiling test write-down of $12.9 million pre-tax. 5.During the first quarter of 2020, we recorded a non-cash ceiling test write-down of $267.8 million pre-tax ($220.8 million, net of tax). We also recorded total expense of $17.6 million related to the abandonment of salt water disposal assets, $407.1 million related to the write-down of the SCR drilling rigs, $3.0 million related to the write-down of other miscellaneous drilling equipment, and $64.0 million related to the write-down of mid-stream assets. 6.During the second quarter of 2020, we recorded a non-cash ceiling test write-down of $109.3 million pre-tax. 7.During the two months ended August 31, 2020, we recorded a non-cash test write-down of $16.6 million pre-tax and $1.2 million related to the abandonment of other miscellaneous drilling equipment. We also recorded $141.0 million gain in reorganization items, net.