Stock-Based Compensation Plans - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 65,000,000	$ 55,000,000	$ 57,000,000
Recognized income tax benefits related to stock-based compensation	31,000,000	29,000,000	30,000,000
Shares under equity incentive compensation plan for future grant	4,398,496	4,874,542
Directors Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under deferred compensation plans	12,033	14,185
Shares issued in connection with deferred compensation plans	211,655
Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued	85,761	0	151,014
Common stock authorized for issuance	2,500,000
Cash received from exercise of stock options	8,607,000		10,117,000
Stock Option Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Stock options exercisable period, maximum	10 years 1 day
Cash realized from exercise of stock options	127,000,000	172,000,000	153,000,000
Tax benefits realized from exercise of stock options	9,000,000	12,000,000	8,000,000
Intrinsic value of stock options exercised	26,000,000	34,000,000	21,000,000
Total grant date fair value of stock options vested			17,000,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	4 years
Unrecognized compensation cost expected to be recognized over a weighted-average period (in years)	1 year
Unrecognized compensation cost related to non-vested awards	19,000,000
Shares issued	221,822	269,755	453,908
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value	24,765,000	27,716,000	36,969,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested awards	7,000,000
Shares issued	299,525	315,316	278,505
Weighted-average grant date fair value	$ 33,406,000	$ 32,380,000	$ 22,139,000
Deferred Bonus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issuable under deferred compensation plans	29,297	33,046

Employee service share based compensation cash received from employee stock ownership plan.

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Share Based Compensation Arrangement By Share Based Payment Award Award Expiration Period

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Share based compensation arrangement by share based payment award options vested in period weighted average grant date fair value.

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Share based compensation arrangement by share based payment award stock issued in period weighted average grant date fair value.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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Number of share instruments newly issued under a share-based compensation plan.

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