Income Taxes (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Taxes [Abstract]
Income Tax Expense (Benefit)		$ 59	$ 37	$ 1,836	$ 207
Income (loss) from continuing operations before income taxes		$ (52)	$ (90)	(7,450)	(843)
Effective Income Tax Rate Reconciliation, Percent		114.30%	40.80%
Other Tax Expense (Benefit)		$ 29
Impairments and other charges	[1]	$ 0	$ 381	$ 3,189	$ 1,895

[1] Impairments and other charges are as follows:-For the three months ended September 30, 2015, includes $228 million attributable to Completion and Production, $138 million attributable to Drilling and Evaluation, and $15 million attributable to Corporate and other. -For the nine months ended September 30, 2016, includes $2.0 billion attributable to Completion and Production, $1.1 billion attributable to Drilling and Evaluation, and $8 million attributable to Corporate and other. -For the nine months ended September 30, 2015, includes $949 million attributable to Completion and Production, $865 million attributable to Drilling and Evaluation, and $81 million attributable to Corporate and other.