Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011	Sep. 30, 2010
Effective Tax Rate Reconciliation [Abstract]
Statutory U.S. income tax rate		35.00%	35.00%
Effects of foreign operations, including foreign tax credits		7.00%	19.00%
Change in permanent reinvestment assertion		7.00%
Adjustments to valuation allowances		11.00%
Tax law changes		2.00%	2.00%
Other adjustments to effective tax rate		2.00%	(1.00%)
Effective income tax rate for continuing operations		64.00%	55.00%
Effects of foreign operations [Abstract]
Statutory Income Tax rate in Libya		in excess of 90 percent
Tax effect of subsidary restructuring		$ 122
Change In Permanent Reinvestmetn Assertion [Abstract]
U.S. deferred tax on foreign undistributed earnings		716
Foreign source income		2,046
Change in foreign valuation allowances	227	(228)
United States tax credit on foreign tax		488
Valuation Allowance Abstract
Change in foreign valuation allowances	227	(228)
Change in state valuation allowances		18
Tax Law Change [Abstract]
Deferred tax expense due to foreign tax law change		15
Deferred tax expense due to state tax law change		32
Deferred tax asset write-off due to health care reform acts			$ 45
Previous UK supplemental tax rate		20.00%
UK supplemental tax rate effective March 2011		32.00%

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Reconciliation of (a) the reported amount of income tax expense attributable to continuing operations for the year to (b) the amount of income tax expense that would result from applying domestic federal statutory rates to pretax income from continuing operations. The estimated amount and the nature of each significant reconciling item shall be disclosed.