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Information on Stock Options Granted and Exercised (Detail) (USD $)
In Millions, except Per Share data, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Weighted-average fair value of options granted per share | $ 4.07 | $ 4.16 | $ 5.36 |
| Cash received from options exercised | $ 35 | $ 96 | $ 35 |
| Tax benefit realized on options exercised | 1 | 7 | 5 |
| Aggregate intrinsic value of options exercised | $ 9 | $ 38 | $ 17 |
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- Definition
The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Tax benefits realized from the exercise of stock options resulting in reductions in the entity's income taxes, which increases net cash provided by operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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