CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating revenues:
Total operating revenues	$ 1,124,249,000	$ 2,470,685,000	$ 3,326,997,000
Operating costs and expenses:
Depreciation, depletion, amortization and impairment	670,910,000	1,003,873,000	916,318,000
Impairment of goodwill	395,060,000	17,800,000	211,129,000
Selling, general and administrative	97,611,000	133,513,000	134,071,000
Credit loss expense	5,606,000	5,683,000	0
Merger and integration expenses			2,738,000
Restructuring expenses	38,338,000
Other operating expenses (income), net	7,059,000	(2,305,000)	(17,569,000)
Total operating costs and expenses	2,016,507,000	2,932,261,000	3,649,174,000
Operating loss	(892,258,000)	(461,576,000)	(322,177,000)
Other income (expense):
Interest income	1,254,000	6,013,000	5,597,000
Interest expense, net of amount capitalized	(40,770,000)	(75,204,000)	(51,578,000)
Other	756,000	389,000	750,000
Total other expense	(38,760,000)	(68,802,000)	(45,231,000)
Loss before income taxes	(931,018,000)	(530,378,000)	(367,408,000)
Income tax benefit	(127,326,000)	(104,675,000)	(45,987,000)
Net loss	$ (803,692,000)	$ (425,703,000)	$ (321,421,000)
Net loss per common share:
Basic	$ (4.27)	$ (2.10)	$ (1.47)
Diluted	$ (4.27)	$ (2.10)	$ (1.47)
Weighted average number of common shares outstanding:
Basic	188,013	203,039	218,643
Diluted	188,013	203,039	218,643
Contract Drilling
Operating revenues:
Total operating revenues	$ 669,126,000	$ 1,308,350,000	$ 1,430,492,000
Operating costs and expenses:
Operating costs and expenses	380,822,000	785,355,000	885,704,000
Impairment of goodwill	395,060,000	0	0
Pressure Pumping
Operating revenues:
Total operating revenues	336,111,000	868,694,000	1,573,396,000
Operating costs and expenses:
Operating costs and expenses	310,261,000	724,788,000	1,263,850,000
Directional Drilling
Operating revenues:
Total operating revenues	73,356,000	188,786,000	209,275,000
Operating costs and expenses:
Operating costs and expenses	69,050,000	178,645,000	175,829,000
Other
Operating revenues:
Total operating revenues	45,656,000	104,855,000	113,834,000
Operating costs and expenses:
Operating costs and expenses	$ 41,790,000	$ 84,909,000	$ 77,104,000