Condensed Consolidated Statements of Operations - USD ($) shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Condensed Consolidated Statements of Operations [Abstract]
Services	$ 266,093,000	$ 464,545,000	$ 873,985,000	$ 1,684,968,000
Rentals	60,132,000	136,851,000	221,644,000	544,447,000
Total Revenues	326,225,000	601,396,000	1,095,629,000	2,229,415,000
Costs and expenses:
Cost of services (exclusive of items shown separately below)	258,168,000	420,485,000	802,142,000	1,468,264,000
Cost of Services	223,766,000	355,373,000	703,061,000	1,224,931,000
Cost of rentals	34,402,000	65,112,000	99,081,000	243,333,000
Depreciation, depletion, amortization and accretion - services	100,579,000	113,362,000	312,713,000	353,202,000
Depreciation, depletion, amortization and accretion - rentals	22,729,000	33,395,000	79,304,000	114,127,000
General and administrative expenses	86,743,000	123,189,000	270,467,000	403,812,000
Reduction in value of assets	0	755,632,000	462,461,000	1,563,269,000
Income from operations	(141,994,000)	(844,667,000)	(831,458,000)	(1,673,259,000)
Other income (expense):
Interest expense, net	(21,771,000)	(22,622,000)	(68,325,000)	(71,213,000)
Other Nonoperating Income (Expense)	3,667,000	(3,123,000)	22,103,000	(10,620,000)
Income from continuing operations before income taxes	(160,098,000)	(870,412,000)	(877,680,000)	(1,755,092,000)
Income taxes	(46,185,000)	(53,825,000)	(210,599,000)	(161,876,000)
Net income (loss) from continuing operations	(113,913,000)	(816,587,000)	(667,081,000)	(1,593,216,000)
Income (loss) from discontinued operations, net of tax	(4,085,000)	(4,610,000)	(8,577,000)	(24,107,000)
Net income	$ (117,998,000)	$ (821,197,000)	$ (675,658,000)	$ (1,617,323,000)
Earnings per share information:
Continuing Operations	$ (0.75)	$ (5.42)	$ (4.40)	$ (10.60)
Discontinued Operations	(0.03)	(0.03)	(0.06)	(0.16)
Basic and Diluted loss per share	$ (0.78)	(5.45)	(4.46)	(10.76)
Common Stock, Dividends, Per Share, Cash Paid		$ 0.08	$ 0.08	$ 0.24
Weighted average common shares used in computing earnings per share:
Basic	151,707	150,742	151,337	150,372