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Summary of Stock Option Grants (Detail) (USD $)
In Millions, except Per Share data, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2011
Year
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Dec. 31, 2010
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Dec. 31, 2009
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| Stock options grant shares | |||
| Outstanding at beginning of year | 37.4 | 47.8 | 53.4 |
| Granted | 3.9 | 4.5 | 5.6 |
| Exercised | (9.0) | (13.6) | (10.7) |
| Forfeited/expired | (0.6) | (1.3) | (0.5) |
| Outstanding at end of year | 31.7 | 37.4 | 47.8 |
| Exercisable at end of year | 21.9 | 26.4 | 35.4 |
| Stock options grant weighted-average exercise price | |||
| Outstanding at beginning of year | $ 42.47 | $ 38.16 | $ 34.88 |
| Granted | $ 75.97 | $ 63.26 | $ 56.94 |
| Exercised | $ 37.46 | $ 33.84 | $ 31.17 |
| Forfeited/expired | $ 55.00 | $ 46.03 | $ 47.22 |
| Outstanding at end of year | $ 47.77 | $ 42.47 | $ 38.16 |
| Exercisable at end of year | $ 39.53 | ||
| Stock options grant Weighted-average remaining contractual life | |||
| Outstanding at end of year | 5.1 | ||
| Exercisable at end of year | 3.7 | ||
| Stock options grant aggregate intrinsic value | |||
| Outstanding at end of year | $ 1,667.6 | ||
| Exercisable at end of year | $ 1,328.8 | ||
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- Definition
The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
For presentations that combine terminations, 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 or that expired. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The combined weighted average exercise price associated with stock options during the period that have either lapsed or been forfeited. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Net number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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