Property Transactions Property Transactions - Discontinued Operations (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]
Oil and Gas Sales	$ 37	$ 208	$ 357
Income Before Income Taxes	12	101	215
Income Tax Expense	6	55	174
Operating Income, Net of Tax	6	46	41
Gain on Sale, Net of Tax	65	16	0
Discontinued Operations, Net of Tax	$ 71	$ 62	$ 41

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Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Overall income (loss) from a disposal group that is classified as a component of the entity, before income tax, reported as a separate component of income before extraordinary items. Includes the following (before income tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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