Significant Accounting Policies (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Share-based compensation expense
Share-based compensation expense	$ 20	$ 26	$ 74	$ 79
Capitalized interest
Capitalized interest costs on construction work in progress	$ 5	$ 20	$ 30	$ 67

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration