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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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

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- Definition

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

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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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No definition available.

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- Definition

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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- Definition

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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- Definition

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

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- Definition

Number of shares issued under share-based payment arrangement.

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Stock-Based Compensation Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 80	$ 76	$ 66
Recognized income tax benefits related to stock-based compensation	$ 17	$ 19	$ 24
Shares under equity incentive compensation plan for future grant	3,100,665	3,742,478
Stock Options Outstanding, Granted	187,088	164,244	116,852
Directors Stock Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issuable under deferred compensation plans	3,809	5,043
Shares issued in connection with deferred compensation plans	295,182
Deferred Bonus Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issuable under deferred compensation plans	14,304	16,491
Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares under equity incentive compensation plan for future grant	2,233,581
Shares issued	77,170	71,676	58,167
Cash received from exercise of stock options	$ 12	$ 11	$ 10
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years	3 years	3 years	4 years
Shares issued	0	0	0
Unrecognized compensation cost expected to be recognized over a weighted-average period (in years)	1 year
Restricted Stock Units (RSUs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued	480,949	448,487	348,512
Weighted-average grant date fair value	$ 81	$ 74	$ 66
Unrecognized compensation cost related to non-vested awards	$ 29
Stock Option Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Stock options exercisable period, maximum	10 years 1 day
Cash realized from exercise of stock options	$ 3	9	60
Intrinsic value of stock options exercised	$ 1	$ 3	$ 16