v2.4.0.6

Equity - Additional Information (Detail) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2011 | Dec. 31, 2010
Preferred Stock, Authorized | 500,000,000 |  | 500,000,000 |
Preferred Stock, Par value | $ 0.01 |  | $ 0.01 |
Preferred Stock, Issued | 0 |  | 0 |
Preferred Stock, Outstanding | 0 |  | 0 |
Noncontrolling interests | $ 510,000,000 | [1] | $ 547,000,000 | [1]
Noncontrolling Interest amounts related to operating joint ventures, largest | 482,000,000 |  | 520,000,000 |
Ownership level in company stock that would potentially trigger anti- takeover effects of preferred share purchase rights | 15 percent or more |  |  |
Preferred stock, exercise price of one one - hundredth share | $ 300 |  |  |
[1] | Certain amounts have been restated to reflect a prior period adjustment. See Note 21-Accumulated Other Comprehensive Income, in the Notes to Consolidated Financial Statements.

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