Incentive Plans - Schedule of Activity Relating to RSUs and DSUs (Detail)	6 Months Ended
Jun. 30, 2021 $ / shares shares
RSUs [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Units, Beginning Balance \| shares	9,266,344
Units, Granted \| shares	2,903,430
Units, Forfeited \| shares	(90,990)
Units, Settled \| shares	(3,735,389)
Units, Ending Balance \| shares	8,343,395
Weighted Average Grant Date Fair Value, Beginning Balance \| $ / shares	$ 42.96
Weighted Average Grant Date Fair Value, Granted \| $ / shares	43.11
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	40.97
Weighted Average Grant Date Fair Value, Settled \| $ / shares	47.42
Weighted Average Grant Date Fair Value, Ending Balance \| $ / shares	$ 41.03
DSUs [Member]
Share-based compensation arrangement by share-based payment award [Line Items]
Units, Beginning Balance \| shares	478,800
Units, Granted \| shares	39,081
Units, Settled \| shares	(185,657)
Units, Ending Balance \| shares	332,224
Weighted Average Grant Date Fair Value, Beginning Balance \| $ / shares	$ 36.36
Weighted Average Grant Date Fair Value, Granted \| $ / shares	46.51
Weighted Average Grant Date Fair Value, Settled \| $ / shares	35.89
Weighted Average Grant Date Fair Value, Ending Balance \| $ / shares	$ 37.82

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The number of grants made 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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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-Publisher FASB
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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

No definition available.

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