Share-Based Compensation Plans (Narrative) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to unvested RSUs	$ 26
Incentive Compensation Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock that can be awarded under terms of incentive compensation plan, in shares	2.7
Incentive Compensation Plan, termination period, in years	10 years
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Employee stock purchase plan percentage of purchase price on closing price	85.00%
Shares issued Employee Stock Purchase Plan	0.5	0.5	0.4
Shares reserved for future issuances	0.6
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to unvested RSUs that is expected to be recognized over a weighted-average period, Years	2 years 1 month 6 days
Weighted average grant-date fair value	$ 56.65	$ 63.14	$ 51.46
Total fair value of shares distributed	$ 49	$ 56	$ 51
Shares vested but not distributed	1.1

Period from effective date until the Incentive Compensation Plan terminates.

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- Definition

Share-based compensation arrangement by share-based payment award, equity instruments other than options, fair value of awards distributed during the period.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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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.

+ References

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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- 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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- 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

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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