Impairments (Details) (USD $) In Millions, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011
Assets held for sale
Impairment losses	$ 3	$ 28
GSF Britannia, George H. Galloway, GSF Labrador and Searex IV
Assets held for sale
Impairment losses	3	28
Loss per diluted share from continuing operations	$ 0.01	$ 0.09
Loss on impairment of assets per diluted share (in dollars per share)	0	0
GSF Britannia, George H. Galloway, GSF Labrador and Searex IV \| Maximum
Assets held for sale
Aggregate losses on asset held for sale tax effect		$ 1

Amount of tax effect on losses for assets held for sale.

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- Definition

Represents the amount of loss per share from continuing operations on assets held for sale at the time of impairment.

+ Details

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- Definition

The loss from impairment charge on assets per each share of dilutive common stock during the reporting period.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 27, 28, 29, 30

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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