Combined Summarized Operating Results For Affiliates (Detail) (Other Investments, USD $) In Millions	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Other Investments
Segment Reporting, Revenue Reconciling Item [Line Items]
Total revenues	$ 291	$ 360	$ 986
Expenses	(214)	(274)	(769)
Depreciation and amortization	(23)	(119)	(121)
Operating profit (loss)	54	(33)	96
Interest income		3	10
Interest expense	(44)	(53)	(118)
Net income (loss)	$ 10	$ (83)	$ (12)

The amount of the cost of sales reported by an equity method investment of the entity.

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Equity Method Investment Summarized Financial Information Depreciation And Amortization

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Equity Method Investment Summarized Financial Information Interest Expense

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Equity Method Investment Summarized Financial Information Investment Income Interest

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- Definition

Equity Method Investment, Summarized Financial Information, Operating Income (Loss)

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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This item represents the disclosure of summarized financial information for unconsolidated subsidiaries and 50 percent-or-less owned entities accounted for using the equity method of accounting. If investments in common stock of corporate joint ventures or other investments accounted for under the equity method are, in the aggregate, material in relation to the financial position or results of operations of an investor, it may be necessary to present summarized information as to assets of the investee, or group of investments for which combined disclosure is appropriate, either by individual financial statement caption or in groups, as appropriate. Such summarized financial information may, at a minimum, include net income or loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph w
-Article 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph g
-Subparagraph 1, 2
-Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph f

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 18
-Paragraph 20
-Subparagraph d

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph bb
-Article 1

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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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