Share-Based Payments - Narrative (Detail)	12 Months Ended
Dec. 31, 2019 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for award	518,000,000
2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized	400,000,000
Maximum shares available per individual during the plan period	20,000,000
Restricted Stock Units (RSUs) [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	3
Portfolio Performance Shares [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	3
Performance Shares [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	3
Total Shareholder Return Units (TSRUs) [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	1
Performance Total Shareholder Return Unit (PTSRUs) [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	1
Share-based Payment Arrangement, Option [Member] \| 2019 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares counted toward maximum	1

Share Based Compensation Arrangement By Share Based Payment Award, Maximum Number of Awards Granted Per Employee

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Shares Counted Toward Maximum Number of Awards Granted Per Employee

+ References

No definition available.

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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.

+ References

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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