Long-Term Compensation - Stock Option and Other Share Based Activity (Detail) (USD $)	12 Months Ended
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Beginning balance	9,879,960
Number of Options, Exercised	(2,060,994)
Number of options, Forfeited/Expired	(305,749)
Number of Options, Ending balance	7,513,217
Weighted Average Exercise Price, Beginning Balance	$ 34.93
Weighted Average Exercise Price, Exercised	$ 24.12
Weighted Average Exercise Price, Forfeited/Expired	$ 56.46
Weighted Average Exercise Price, Ending Balance	$ 37.02
Options Exercisable ,Number of Options Ending balance	6,957,148
Options Exercisable, Weighted Average Exercise Price, Ending Balance	$ 37.76
Options Exercisable, Weighted Average Life (in years)	4 years 6 months 24 days

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Number of share options (or share units) exercised during the current period.

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