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Combination of age and years necessary for retirement provision as related to our equity award program

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and vesting of restricted stock

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Maximum deductibility of annual compensation per employee as mandated by health insurance reform legislation.

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Minimum age required for retirement eligibility as related to our equity award program

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Minimum number of years of service for retirement eligibility as related to our equity award program

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Number of shares of our common stock reserved for issuance under our defined contribution retirement savings plans

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Number of year for stock options to vest

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Percentage of the retirement and savings plan's assets invested in our common stock as compared to company's outstanding shares at year-end

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Percentage of retirement and savings plan's assets invested in our company common stock

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Number of common shares available for grant assuming all options

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Share Based Compensation By Share Based Payment Award, Equity Instruments Other Than Options, Percent Of Stock With Performance Based Conditions

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Shares Of Retirement And Savings Plans Invested In Our Companys Common Stock

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Amount of cost for defined contribution plan.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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EMPLOYEE BENEFIT PLANS - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee retirement and savings plan cost		$ 197,000,000	$ 217,000,000	$ 196,000,000
Closing stock price (in dollars per share)	$ 286.48
Percentage of retirement and savings plan's assets invested in our company common stock		12.00%
Shares of retirement and savings plans invested in company's common stock (in shares)	1.8	1.8
Percentage of the retirement and savings plan's assets invested in our common stock as compared to company's outstanding shares at year-end		1.30%
Number of shares of our common stock reserved for issuance (in shares)	2.0	2.0
Combination of age and years necessary for retirement provision as related to our equity award program		65 years
Minimum age required for retirement eligibility as related to our equity award program		55 years
Minimum number of years of service for retirement eligibility as related to our equity award program		5 years
Limitations on deductibility of excess annual employee compensation as mandated by health insurance reforms		$ 500,000
Employee service share based compensation tax benefit realized from exercise of stock options and restricted stock vesting		$ 49,000,000	68,000,000	53,000,000
Common stock shares reserved for stock award plans (in shares)	13.1	13.1
Fair value of shares vested		$ 298,000,000	306,000,000	253,000,000
Outstanding intrinsic value of stock options	$ 48,000,000	$ 48,000,000
Weighted-average remaining contractual term, years		5 years
Exercisable stock options intrinsic value	$ 19,000,000	$ 19,000,000
Exercisable stock options weighted-average remaining contractual term, years		4 years 1 month 6 days
Total intrinsic value of stock options exercised		$ 43,000,000	44,000,000	18,000,000
Cash received from stock options exercises		$ 50,000,000	63,000,000	$ 14,000,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation modification expense			$ 29,000,000
Weighted-average grant date fair value of restricted stock awards (in USD per share)		$ 276.62	$ 222.35	$ 168.12
Percent of stock with performance-based conditions	12.00%	12.00%
Total compensation expense not yet recognized related to nonvested restricted stock	$ 156,000,000	$ 156,000,000
Compensation expense over a weighted-average period, years		1 year 9 months 18 days
Employee Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense not yet recognized related to nonvested restricted stock	$ 14,000,000	$ 14,000,000
Compensation expense over a weighted-average period, years		1 year 8 months 12 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of year for stock options to vest		1 year
Number of years for stock options to expire		7 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of year for stock options to vest		3 years
2011 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available for future grants if all grants are options (in shares)	2.0	2.0
2011 Plan \| Employee Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available for future grants if all grants are options (in shares)	4.7	4.7