The aggregate grant date fair value of the awards made under the stock-based compensation plan.

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Number of share price targets under share based payment arrangement.

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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.

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

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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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- 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).

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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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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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- Definition

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

+ References

No definition available.

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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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No definition available.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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Percentage of vesting of award under share-based payment arrangement.

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Share-Based Payments and Employee Benefits - Performance-Based LTIP Units (Details) $ / shares in Units, $ in Millions	1 Months Ended			12 Months Ended
	Jan. 31, 2022 $ / shares shares	Nov. 30, 2021 shares	Jul. 31, 2021 item $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award
Compensation expense recognition period (in years)				3 years 7 months 6 days
Performance Shares and Special Performance-Based LTIP Units [Member]
Unvested Shares
Beginning balance	2,776,242			2,126,597
Granted (in shares)				1,471,944
Vested				(299,832)
Forfeited/cancelled				(522,467)
Ending balance				2,776,242	2,126,597
Weighted Average Grant-Date Fair Value
Beginning balance \| $ / shares	$ 19.21			$ 19.29
Granted \| $ / shares				19.69
Vested (in dollars per share) \| $ / shares				17.07
Forfeited/cancelled \| $ / shares				22.10
Ending balance \| $ / shares				$ 19.21	$ 19.29
Performance LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period				3 years
Vesting (as a percent)			50.00%
Share price targets \| item			4
Fair value of awards on grant date \| $				$ 29.0	$ 11.1	$ 9.3
Compensation expense recognition period (in years)			7 years	4 years
Expected volatility					15.00%
Dividend yield				2.60%	2.30%
Risk-free interest rate					1.30%
Total-grant date fair value for vested awards \| $				$ 5.1	$ 4.6
Unvested Shares
Granted (in shares)			844,070	627,874	593,100	478,411
Weighted Average Grant-Date Fair Value
Granted \| $ / shares			$ 23.08	$ 15.14	$ 18.67	$ 19.49
Performance LTIP Units \| Subsequent Event
Unvested Shares
Granted (in shares)	21,705
Forfeited/cancelled	(469,624)
Performance LTIP Units \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Vesting (as a percent)				50.00%
Performance LTIP Units \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Vesting (as a percent)			25.00%	50.00%
Performance LTIP Units \| Share-based Compensation Award, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Vesting (as a percent)			25.00%
Performance LTIP Units \| If Positive Absolute Total Shareholder Return, Not Achieved
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period				3 years
Performance LTIP Units \| If Positive Absolute Total Shareholder Return, Achieved
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period				7 years
Special Performance-Based LTIP Units [Member]
Unvested Shares
Forfeited/cancelled		(506,182)
Minimum \| Performance LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award
Expected volatility				31.00%		19.00%
Dividend yield						2.30%
Risk-free interest rate				0.20%		2.30%
Maximum \| Performance LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award
Expected volatility				34.00%		23.00%
Dividend yield						2.50%
Risk-free interest rate				1.00%		2.60%