Commitments and Contingencies (Commitments) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012 Inventories	Jul. 31, 2012 Inventories Operating Leases, Purchase Power Contracts Subsequent Event	Jun. 30, 2012 Environmental Indemnities
Commitments and Guarantees
Estimated additional commitments, 2014		$ 51
Estimated additional commitments, 2015	21	53
Estimated additional commitments, 2016	45	50
Estimated additional commitments, thereafter	944	199
Maximum liability under indemnity per Mountainview purchase agreement for damages and other amounts			$ 60

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The maximum aggregate potential liability under the purchase agreement for damages and other amounts in connection with environmental liabilities.

No definition available.

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Amount of the recorded unconditional purchase obligation maturing after the fifth rolling twelve months following the latest balance sheet presented.

No definition available.

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Amount of the recorded unconditional purchase obligation maturing in the fifth rolling twelve months following the latest balance sheet presented.

No definition available.

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Amount of the recorded unconditional purchase obligation maturing in the fourth rolling twelve months following the latest balance sheet presented.

No definition available.

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Amount of the recorded unconditional purchase obligation maturing in the third rolling twelve months following the latest balance sheet presented.

No definition available.

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