Segment Information (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended			12 Months Ended
		Sep. 30, 2016		Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015		Dec. 31, 2014
Segment Reporting Information [Line Items]
Net Operating Revenues		$ 1,356		$ 2,237	$ 4,343	$ 7,421
Operating Income (Loss)		(945)		(98)	(1,852)	(512)
Depreciation and Amortization		242		298	741	925
Corporate and Research and Development		(33)		(56)	(119)	(179)
Restructuring Charges		(22)		(49)	(150)	(159)
Litigation Charges, Net		9		0	190	112
Gain (Loss) on Disposition of Business		0		0	(1)	(2)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		1,356		2,237	4,343	7,421
Operating Income (Loss)		(111)		80	(334)	345
Depreciation and Amortization		238		292	729	907
Operating Segments [Member] | Core Regional Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		1,258		2,051	4,017	6,855
Operating Income (Loss)		(92)		64	(272)	315
Depreciation and Amortization		216		264	662	823
Operating Segments [Member] | Drilling Rigs [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		98		186	326	566
Operating Income (Loss)		(19)		16	(62)	30
Depreciation and Amortization		22		28	67	84
Corporate and Research and Development [Member]
Segment Reporting Information [Line Items]
Depreciation and Amortization		4		6	12	18
Corporate and Research and Development		(63)		(101)	(226)	(326)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Impairment of Long-Lived Assets and Other Related Charges		740	[1]	(17)		951	[1]	$ (208)
Goodwill, Impairment Loss						(20)
Restructuring Charges	[2]	(22)		(49)	(150)	(159)
Litigation Charges, Net		9			190	(112)
Gain (Loss) on Disposition of Business					(1)	(2)
Other Items	[3]			(11)		(30)
North America [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		449		824	1,393	2,795
Operating Income (Loss)		(95)		(54)	(324)	(156)
Depreciation and Amortization		55		87	167	289
MENA/ Asia Pacific [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		329		445	1,090	1,494
Operating Income (Loss)		(8)		2	(4)	45
Depreciation and Amortization		60		62	181	193
Europe/ SSA/ Russia [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		225		361	725	1,196
Operating Income (Loss)		(3)		43	(3)	179
Depreciation and Amortization		45		52	141	155
Latin America [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Revenues		255		421	809	1,370
Operating Income (Loss)		14		73	59	247
Depreciation and Amortization		$ 56		63	$ 173	186
2015 Plan [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(49)		(159)
2015 Plan [Member] | Core Regional Segments [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(35)		(136)
2015 Plan [Member] | Drilling Rigs [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(6)		(12)
2015 Plan [Member] | Corporate and Research and Development [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(8)		(11)
2015 Plan [Member] | North America [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(9)		(38)
2015 Plan [Member] | MENA/ Asia Pacific [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(5)		(40)
2015 Plan [Member] | Europe/ SSA/ Russia [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				(11)		(32)
2015 Plan [Member] | Latin America [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Restructuring Charges				$ (10)		$ (26)

[1] Includes $436 million in long-lived asset impairments, $198 million in inventory write-downs, $62 million in accounts receivable reserves and write-offs, and $44 million of other asset write-offs and charges.

[2] Includes restructuring charges of $22 million: $10 million in Latin America, $5 million in North America, $5 million in MENA/Asia Pacific, and $2 million in Corporate and Research and Development.

[3] Includes professional and other fees of $7 million, facility closure fees of $2 million, and divestiture related charges of $2 million.