Supplemental Condensed Consolidated Financial Information (Condensed Consolidating Statements of Operation) (Details) - USD ($) $ in Thousands	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, 2019
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 32,846	$ 65,574	$ 100,682	$ 89,007	$ 122,376	$ 164,358		$ 155,439	$ 165,146	$ 189,691			$ 276,957		$ 674,634
Expenses
Operating costs											$ 81,277		237,546		384,728
Depreciation, depletion, and amortization											27,962		115,496		275,573
Impairments											26,063	[1]	867,814	[2]	625,716	[3]
Loss on abandonment of assets											0		18,733		0
General and administrative											6,702		42,766		38,246
(Gain) loss on disposition of assets											(619)		(89)		3,502
Total operating expenses											141,385		1,282,266		1,327,765
Income (loss) from operations											(7,857)		(1,005,309)		(653,131)
Interest, net											(3,275)		(22,824)		(37,012)
Write off of Deferred Debt Issuance Cost											0		(2,426)		0
Gain (loss) on derivatives											(985)		(10,704)		4,225
Reorganization Items											(2,273)		133,975		0
Other											100		2,034		(236)
Income (loss) before income taxes											(14,290)		(905,254)		(686,154)
Income tax benefit											(302)		(14,630)		(132,326)
Equity in net earnings from investment in subsidiaries, net of taxes													0		0
Net loss											(13,988)		(890,624)		(553,828)
Less: net income attributable to non-controlling interest											4,152		40,388		51
Net income (loss) attributable to Unit Corporation	$ (8,968)	$ 55,131	$ (9,172)	$ (215,649)	$ (770,494)	$ (334,980)	[4]	$ (206,886)	$ (8,509)	$ (3,504)	$ (18,140)		(931,012)		(553,879)
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Revenues													(14,536)		(47,485)
Expenses
Operating costs													(14,537)		(47,485)
Depreciation, depletion, and amortization													0		0
Impairments													0		0
Loss on abandonment of assets													0
General and administrative													0		0
(Gain) loss on disposition of assets													0		0
Total operating expenses													(14,537)		(47,485)
Income (loss) from operations													1		0
Interest, net													0		0
Write off of Deferred Debt Issuance Cost													0
Gain (loss) on derivatives													0		0
Reorganization Items													0
Other													0		0
Income (loss) before income taxes													1		0
Income tax benefit													0		0
Equity in net earnings from investment in subsidiaries, net of taxes													1,241,120		508,439
Net loss													1,241,121		508,439
Less: net income attributable to non-controlling interest													(40,388)		(51)
Net income (loss) attributable to Unit Corporation													1,281,509		508,490
Parent
Condensed Financial Statements, Captions [Line Items]
Revenues													0		0
Expenses
Operating costs													0		0
Depreciation, depletion, and amortization													1,819		7,707
Impairments													0		0
Loss on abandonment of assets													0
General and administrative													0		0
(Gain) loss on disposition of assets													1,479		(11)
Total operating expenses													3,298		7,696
Income (loss) from operations													(3,298)		(7,696)
Interest, net													(20,936)		(35,466)
Write off of Deferred Debt Issuance Cost													(2,426)
Gain (loss) on derivatives													(10,704)		4,225
Reorganization Items													373,151
Other													79		786
Income (loss) before income taxes													335,866		(38,151)
Income tax benefit													(14,630)		7,238
Equity in net earnings from investment in subsidiaries, net of taxes													(1,241,120)		(508,439)
Net loss													(890,624)		(553,828)
Less: net income attributable to non-controlling interest													40,388		51
Net income (loss) attributable to Unit Corporation													(931,012)		(553,879)
Combined Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenues													176,962		494,180
Expenses
Operating costs													171,476		256,024
Depreciation, depletion, and amortization													84,306		220,203
Impairments													803,852		622,676
Loss on abandonment of assets													18,733
General and administrative													42,766		38,246
(Gain) loss on disposition of assets													(1,550)		3,673
Total operating expenses													1,119,583		1,140,822
Income (loss) from operations													(942,621)		(646,642)
Interest, net													0		0
Write off of Deferred Debt Issuance Cost													0
Gain (loss) on derivatives													0		0
Reorganization Items													(168,160)
Other													1,906		(1,086)
Income (loss) before income taxes													(1,108,875)		(647,728)
Income tax benefit													0		(139,564)
Equity in net earnings from investment in subsidiaries, net of taxes													0		0
Net loss													(1,108,875)		(508,164)
Less: net income attributable to non-controlling interest													0		0
Net income (loss) attributable to Unit Corporation													(1,108,875)		(508,164)
Combined Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenues													114,531		227,939
Expenses
Operating costs													80,607		176,189
Depreciation, depletion, and amortization													29,371		47,663
Impairments													63,962		3,040
Loss on abandonment of assets													0
General and administrative													0		0
(Gain) loss on disposition of assets													(18)		(160)
Total operating expenses													173,922		226,732
Income (loss) from operations													(59,391)		1,207
Interest, net													(1,888)		(1,546)
Write off of Deferred Debt Issuance Cost													0
Gain (loss) on derivatives													0		0
Reorganization Items													(71,016)
Other													49		64
Income (loss) before income taxes													(132,246)		(275)
Income tax benefit													0		0
Equity in net earnings from investment in subsidiaries, net of taxes													0		0
Net loss													(132,246)		(275)
Less: net income attributable to non-controlling interest													40,388		51
Net income (loss) attributable to Unit Corporation													$ (172,634)		$ (326)

[1] During the Successor Period of 2020, we recorded non-cash ceiling test write-downs on our oil and natural gas properties of $26.1 million pre-tax

[2] During the Predecessor Period of 2020, we recorded non-cash ceiling test write-downs on our oil and natural gas properties of $393.7 million, pre-tax ($346.6 million, net of tax). Impairment for contract drilling equipment includes a $410.1 million pre-tax write-down for SCR drilling rigs and other drilling equipment. Impairment for mid-stream assets includes a $64.0 million pre-tax write-down for certain long-lived asset groups.

[3] We incurred non-cash ceiling test write-downs of our oil and natural gas properties of $559.4 million pre-tax ($422.4 million, net of tax). We also recognized goodwill impairment charges of $62.8 million pre-tax ($59.8 million, net of tax).

[4] 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.