Oman Investment (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
payments to fund long term loans to consolidated variable interest entity	$ 2
Oman Investment (Textual) [Abstract]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	55.00%
Amount paid for our interest in the mining rights	16	0
Potential additional payment to increase mining capacity	19
Percentage of noncontrolling owners in VIE	45.00%
Noncontrolling Interest in Variable Interest Entity	13
Gain or loss recognized upon initial consolidation of VIE	0
Co-venturer [Member]
Notes Payable, Related Parties, Noncurrent	$ 2

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payments to fund long term loans to consolidated variable interest entity which is eliminated in consolidation

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- Definition

Potential additional payment to increase mining capacity.

+ References

No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

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The amount for notes payable (written promise to pay), payable to related parties, which are due after one year (or one business cycle).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 57

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- Definition

The cash outflow from the purchase of mining and mining related assets during the period.

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The gain (loss) recognized on initial consolidation of a variable interest entity (VIE) when the VIE is not a business (as defined).

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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