STOCK-BASED COMPENSATION. (Detail) (USD $) In Millions, except Share data	6 Months Ended
Jun. 30, 2011
Stock option rollforward elements
Outstanding at beginning of year	37,759,580
Exercised	(2,200,462)
Forfeited	(260,560)
Outstanding at end of period	38,252,166
Exercisable at end of period	19,638,524
Weighted-average exercise price of options outstanding at beginning of year (in dollars per option)	$ 41.34
Weighted-average exercise price of options exercised (in dollars per option)	$ 32.85
Weighted-average exercise price of options forfeited (in dollars per option)	$ 48.12
Weighted-average exercise price of options outstanding at end of period (in dollars per option)	$ 44.01
Weighted-average exercise price of options exercisable at end of period (in dollars per option)	$ 38.09
Nonvested restricted shares and restricted stock units rollforward
Weighted-average fair value of nonvested restricted shares and restricted stock units at beginning of year (in dollars per share)	$ 46.92
Weighted-average fair value of restricted shares and restricted stock units granted to employees and directors (in dollars per share)	$ 69.95
Weighted-average fair value of restricted shares and restricted stock units vested (in dollars per share)	$ 53.42
Weighted-average fair value of restricted shares and restricted stock units forfeited (in dollars per share)	$ 47.81
Weighted-average fair value of nonvested restricted shares and restricted stock units at end of period (in dollars per share)	$ 50.87
Future stock-based compensation expense
Third quarter 2011 (dollars)	$ 24.5
Fourth quarter 2011 (dollars)	19.5
2012 (dollars)	60.1
2013 through 2016 (dollars)	58.9
Total (dollars)	$ 163.0
Semiannual [Member]
Stock option rollforward elements
Grants	2,894,480
Weighted-average exercise price of option grants (in dollars per option)	$ 70.33
Reload [Member]
Stock option rollforward elements
Grants	27,278
Weighted-average exercise price of option grants (in dollars per option)	$ 67.11
New hire [Member]
Stock option rollforward elements
Grants	23,850
Weighted-average exercise price of option grants (in dollars per option)	$ 63.93
Non-employee director [Member]
Stock option rollforward elements
Grants	8,000
Weighted-average exercise price of option grants (in dollars per option)	$ 64.94
Restricted shares [Member]
Nonvested restricted shares and restricted stock units rollforward
Nonvested at beginning of year	638,532
Granted to employees and directors	128,975
Vested	(8,675)
Forfeited	(13,490)
Nonvested at end of period	745,342
Restricted stock units [Member]
Nonvested restricted shares and restricted stock units rollforward
Nonvested at beginning of year	368,201
Granted to employees and directors	73,550
Vested	(11,032)
Forfeited	(38,103)
Nonvested at end of period	392,616

A positive value represents the unrecognized cost of awards outstanding at the balance sheet date under share-based compensation plans that will be recognized in the second January subsequent to the balance sheet date through each awards vesting date.

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A positive value represents the unrecognized cost of awards outstanding at the balance sheet date under share-based compensation plans that will be recognized during the next January through December period subsequent to the balance sheet date

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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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 weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period.

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Gross number of share options (or share units) granted during the period.

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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 stock options awarded under the plan during the reporting period.

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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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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.

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

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