Supplemental Condensed Consolidated Financial Information (Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands		Dec. 31, 2020	Sep. 01, 2020	Aug. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents		$ 12,145			$ 571	$ 6,452
Accounts receivable		57,846			82,656
Materials and supplies		0			449
Current derivative assets		0			633
Income taxes receivable		1,150			1,756
Assets held for sale		0			5,908
Prepaid expenses and other		11,212			13,078
Total current assets		82,922			105,051
Oil and Gas Property [Abstract]
Proved properties		238,581	$ 238,284	$ 6,539,816	6,341,582
Unproved properties not being amortized		1,591	0	30,205	252,874
Drilling equipment		63,687	63,458	1,285,024	1,295,713
Gas gathering and processing equipment		251,404	250,098	833,788	824,699
Saltwater disposal systems		0	0	43,541	69,692
Land and building		32,635	32,635	59,080	59,080
Transportation equipment		3,130	3,314	15,577	29,723
Other		9,961	9,958	57,427	57,992
Property, plant and equipment, gross, total		600,989			8,931,355
Less accumulated depreciation, depletion, amortization, and impairment		54,189			6,978,669
Net property and equipment		546,800			1,952,686
Intercompany receivable					0
Investments					0
Right of use asset		5,592			5,673
Other assets					26,642
Total assets	[1]	649,703			2,090,052
Current liabilities:
Accounts payable		40,829			84,481
Accrued liabilities		21,743			46,562
Operating Lease, Liability, Current		4,075			3,430
Current portion of long-term debt (Note 9)		600			108,200
Current portion of other long-term liabilities		11,168			17,376
Total current liabilities		80,347			260,049
Intercompany debt					0
Long-term debt less debt issuance costs		98,400			663,216
Non-current derivative liabilities		4,659			27
Long-term operating lease payments		1,445			2,071
Other long-term liabilities		39,259			95,341
Deferred income taxes		0			13,713
Total shareholders' equity		425,593	$ 439,523	$ 171,180	1,055,635	1,593,444
Total liabilities and shareholders' equity	[1]	$ 649,703			2,090,052
Consolidating Adjustments
Current assets:
Cash and cash equivalents					0	0
Accounts receivable					(9,447)
Materials and supplies					0
Current derivative assets					0
Income taxes receivable					0
Assets held for sale					0
Prepaid expenses and other					0
Total current assets					(9,447)
Oil and Gas Property [Abstract]
Proved properties					0
Unproved properties not being amortized					0
Drilling equipment					0
Gas gathering and processing equipment					0
Saltwater disposal systems					0
Land and building					0
Transportation equipment					0
Other					0
Property, plant and equipment, gross, total					0
Less accumulated depreciation, depletion, amortization, and impairment					0
Net property and equipment					0
Intercompany receivable					(1,048,785)
Investments					(865,252)
Right of use asset					(54)
Other assets					0
Total assets					(1,923,538)
Current liabilities:
Accounts payable					(7,291)
Accrued liabilities					(2,156)
Operating Lease, Liability, Current					(6)
Current portion of long-term debt (Note 9)					0
Current portion of other long-term liabilities					0
Total current liabilities					(9,453)
Intercompany debt					(1,048,785)
Long-term debt less debt issuance costs					0
Non-current derivative liabilities					0
Long-term operating lease payments					(48)
Other long-term liabilities					0
Deferred income taxes					0
Total shareholders' equity					(865,252)
Total liabilities and shareholders' equity					(1,923,538)
Parent
Current assets:
Cash and cash equivalents					503	403
Accounts receivable					2,645
Materials and supplies					0
Current derivative assets					633
Income taxes receivable					1,756
Assets held for sale					0
Prepaid expenses and other					2,019
Total current assets					7,556
Oil and Gas Property [Abstract]
Proved properties					0
Unproved properties not being amortized					0
Drilling equipment					0
Gas gathering and processing equipment					0
Saltwater disposal systems					0
Land and building					0
Transportation equipment					9,712
Other					28,927
Property, plant and equipment, gross, total					38,639
Less accumulated depreciation, depletion, amortization, and impairment					33,794
Net property and equipment					4,845
Intercompany receivable					1,048,785
Investments					865,252
Right of use asset					46
Other assets					8,107
Total assets					1,934,591
Current liabilities:
Accounts payable					12,259
Accrued liabilities					28,003
Operating Lease, Liability, Current					20
Current portion of long-term debt (Note 9)					108,200
Current portion of other long-term liabilities					3,003
Total current liabilities					151,485
Intercompany debt					0
Long-term debt less debt issuance costs					646,716
Non-current derivative liabilities					27
Long-term operating lease payments					25
Other long-term liabilities					12,553
Deferred income taxes					68,150
Total shareholders' equity					1,055,635
Total liabilities and shareholders' equity					1,934,591
Combined Guarantor Subsidiaries
Current assets:
Cash and cash equivalents					68	208
Accounts receivable					64,805
Materials and supplies					449
Current derivative assets					0
Income taxes receivable					0
Assets held for sale					5,908
Prepaid expenses and other					3,373
Total current assets					74,603
Oil and Gas Property [Abstract]
Proved properties					6,341,582
Unproved properties not being amortized					252,874
Drilling equipment					1,295,713
Gas gathering and processing equipment					0
Saltwater disposal systems					69,692
Land and building					59,080
Transportation equipment					16,621
Other					29,065
Property, plant and equipment, gross, total					8,064,627
Less accumulated depreciation, depletion, amortization, and impairment					6,537,731
Net property and equipment					1,526,896
Intercompany receivable					0
Investments					0
Right of use asset					1,733
Other assets					9,094
Total assets					1,612,326
Current liabilities:
Accounts payable					61,002
Accrued liabilities					14,024
Operating Lease, Liability, Current					1,009
Current portion of long-term debt (Note 9)					0
Current portion of other long-term liabilities					7,313
Total current liabilities					83,348
Intercompany debt					1,047,599
Long-term debt less debt issuance costs					0
Non-current derivative liabilities					0
Long-term operating lease payments					690
Other long-term liabilities					74,662
Deferred income taxes					(54,437)
Total shareholders' equity					460,464
Total liabilities and shareholders' equity					1,612,326
Combined Non-Guarantor Subsidiaries
Current assets:
Cash and cash equivalents					0	$ 5,841
Accounts receivable					24,653
Materials and supplies					0
Current derivative assets					0
Income taxes receivable					0
Assets held for sale					0
Prepaid expenses and other					7,686
Total current assets					32,339
Oil and Gas Property [Abstract]
Proved properties					0
Unproved properties not being amortized					0
Drilling equipment					0
Gas gathering and processing equipment					824,699
Saltwater disposal systems					0
Land and building					0
Transportation equipment					3,390
Other					0
Property, plant and equipment, gross, total					828,089
Less accumulated depreciation, depletion, amortization, and impairment					407,144
Net property and equipment					420,945
Intercompany receivable					0
Investments					0
Right of use asset					3,948
Other assets					9,441
Total assets					466,673
Current liabilities:
Accounts payable					18,511
Accrued liabilities					6,691
Operating Lease, Liability, Current					2,407
Current portion of long-term debt (Note 9)					0
Current portion of other long-term liabilities					7,060
Total current liabilities					34,669
Intercompany debt					1,186
Long-term debt less debt issuance costs					16,500
Non-current derivative liabilities					0
Long-term operating lease payments					1,404
Other long-term liabilities					8,126
Deferred income taxes					0
Total shareholders' equity					404,788
Total liabilities and shareholders' equity					$ 466,673

[1] Unit Corporation's consolidated total assets as of December 31, 2020 include current and long-term assets of its variable interest entity (VIE) (Superior) of $45.8 million and $247.8 million, respectively, which can only be used to settle obligations of the VIE. Unit Corporation's consolidated total liabilities as of December 31, 2020 include current and long-term liabilities of the VIE of $28.4 million and $2.6 million, respectively, for which the creditors of the VIE have no recourse to Unit Corporation. Unit Corporation's consolidated total assets as of December 31, 2019 include current and long-term assets of its variable interest entity (VIE) (Superior) of $28.8 million and $434.3 million, respectively, which can only be used to settle obligations of the VIE. Unit Corporation's consolidated total liabilities as of December 31, 2019 include current and long-term liabilities of the VIE of $32.2 million and $26.0 million, respectively, for which the creditors of the VIE have no recourse to Unit Corporation. See Note 19 – Variable Interest Entity Arrangements.