Supplemental Condensed Consolidated Financial Information (Condensed Consolidating Statements of Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 189,691	$ 205,132
Expenses:
Operating costs	103,470	109,233
Depreciation, depletion, and amortization	62,126	57,066
General and administrative	9,741	10,762
(Gain) loss on disposition of assets	1,615	(161)
Total operating costs	176,952	176,900
Income (loss) from operations	12,739	28,232
Interest, net	(8,538)	(10,004)
Loss on derivatives	(6,932)	(6,762)
Other, net	5	6
Income (loss) before income taxes	(2,726)	11,472
Income tax expense (benefit)	(444)	3,607
Equity in net earnings from investment in subsidiaries, net of taxes	0	0
Net income (loss)	(2,282)	7,865
Less: net income attributable to non-controlling interest	1,222	0
Net income (loss) attributable to Unit Corporation	(3,504)	7,865
Consolidating Adjustments [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	(25,112)	(23,327)
Expenses:
Operating costs	(24,052)	(22,893)
Depreciation, depletion, and amortization	0	0
General and administrative	0	0
(Gain) loss on disposition of assets	0	0
Total operating costs	(24,052)	(22,893)
Income (loss) from operations	(1,060)	(434)
Interest, net	0	0
Loss on derivatives	0	0
Other, net	0	0
Income (loss) before income taxes	(1,060)	(434)
Income tax expense (benefit)	0	0
Equity in net earnings from investment in subsidiaries, net of taxes	(9,850)	(21,725)
Net income (loss)	(10,910)	(22,159)
Less: net income attributable to non-controlling interest	0
Net income (loss) attributable to Unit Corporation	(10,910)
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0
Expenses:
Operating costs	0	0
Depreciation, depletion, and amortization	1,934	1,918
General and administrative	0	0
(Gain) loss on disposition of assets	(10)	(30)
Total operating costs	1,924	1,888
Income (loss) from operations	(1,924)	(1,888)
Interest, net	(8,202)	(9,855)
Loss on derivatives	(6,932)	(6,762)
Other, net	5	6
Income (loss) before income taxes	(17,053)	(18,499)
Income tax expense (benefit)	(3,699)	(4,639)
Equity in net earnings from investment in subsidiaries, net of taxes	9,850	21,725
Net income (loss)	(3,504)	7,865
Less: net income attributable to non-controlling interest	0
Net income (loss) attributable to Unit Corporation	(3,504)
Combined Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	144,294	153,809
Expenses:
Operating costs	71,393	73,106
Depreciation, depletion, and amortization	48,466	44,095
General and administrative	9,741	8,229
(Gain) loss on disposition of assets	1,667	(97)
Total operating costs	131,267	125,333
Income (loss) from operations	13,027	28,476
Interest, net	0	0
Loss on derivatives	0	0
Other, net	0	1
Income (loss) before income taxes	13,027	28,477
Income tax expense (benefit)	3,255	7,648
Equity in net earnings from investment in subsidiaries, net of taxes	0	0
Net income (loss)	9,772	20,829
Less: net income attributable to non-controlling interest	0
Net income (loss) attributable to Unit Corporation	9,772
Combined Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	70,509	74,650
Expenses:
Operating costs	56,129	59,020
Depreciation, depletion, and amortization	11,726	11,053
General and administrative	0	2,533
(Gain) loss on disposition of assets	(42)	(34)
Total operating costs	67,813	72,572
Income (loss) from operations	2,696	2,078
Interest, net	(336)	(149)
Loss on derivatives	0	0
Other, net	0	(1)
Income (loss) before income taxes	2,360	1,928
Income tax expense (benefit)	0	598
Equity in net earnings from investment in subsidiaries, net of taxes	0	0
Net income (loss)	2,360	$ 1,330
Less: net income attributable to non-controlling interest	1,222
Net income (loss) attributable to Unit Corporation	$ 1,138