Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2016
(Provision) Benefit for Income Taxes	$ 65	$ (98)	$ 197	$ (136)
Income (Loss) Before Income Taxes	(226)	187	(948)	60
Restructuring Charges	49	154	159	283
Foreign Exchange Related Charges	26	0	68	0
Discrete income before tax				50
Long-Lived Assets Impairment and Other Related Charges	17	0	208	143
Goodwill and Equity Investment Impairment	0	(4)	20	121
Litigation Charges	0	0	112	0
Scenario, Forecast [Member]
Uncertain tax positions, estimated for next twelve months					$ 11
IRAQ
Loss on Contracts	$ 44	10	$ 71	38
Land Drilling and Workover Rig Operations
Long-Lived Assets Impairment and Other Related Charges		143
Goodwill and Equity Investment Impairment		121
2014 Plan [Member]
Restructuring Charges		$ 154		$ 283