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Quarterly Results (Unaudited) (Details 2) (Sell of Discoverer 534 and Jim Cunningham, USD $) In Millions, unless otherwise specified | 3 Months Ended
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Sep. 30, 2012
Sell of Discoverer 534 and Jim Cunningham |
Quarterly results |
Gain (loss) on the sale of assets | $ 51

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- Details
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