Share-Based Compensation Plans - Summary of the status of the Company's RSUs (Details) - Restricted share units (“RSUs”) - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Non-vested share awards
Non-vested at beginning of period (in shares)	3,634	4,208	4,849
Granted (in shares)	1,329	1,306	1,500
Vested (in shares)	(1,426)	(1,661)	(1,943)
Forfeited (in shares)	(228)	(219)	(198)
Non-vested at end of period (in shares)	3,309	3,634	4,208
Fair Value at Date of Grant
Non-vested at beginning of period (in dollars per share)	$ 143	$ 120	$ 104
Granted (in dollars per share)	185	175	141
Vested (in dollars per share)	133	113	97
Forfeited (in dollars per share)	157	131	114
Non-vested at end of period (in dollars per share)	$ 163	$ 143	$ 120

No definition available.

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- Definition

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

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-Publisher FASB
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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.

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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).

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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

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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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

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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.

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