EPS under Basic and Diluted Computations (Parenthetical) (Detail) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Earnings Per Share Disclosure [Line Items]
Antidilutive stock options and restricted stock awards excluded from the calculation of diluted EPS	45	60

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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-Name Accounting Standards Codification

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+ Details