Share-Based Payments - Performance-Based LTIP Units (Details) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense recognition period (in years)	2 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity grants (in shares) \| shares	593,100
Weighted average grant-date fair value (in dollars per share) \| $ / shares	$ 18.67
Vesting period	3 years
Fair value of awards on grant date \| $	$ 11.1
Compensation expense recognition period (in years)	4 years
Expected volatility	15.00%
Dividend yield	2.30%
Risk-free interest rate	1.30%
Performance Shares \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (as a percent)	50.00%
Performance Shares \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (as a percent)	50.00%
Performance Shares \| If Positive Absolute Total Shareholder Return, Not Achieved
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Shares \| If Positive Absolute Total Shareholder Return, Not Achieved \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (as a percent)	50.00%
Performance Shares \| If Positive Absolute Total Shareholder Return, Not Achieved \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting (as a percent)	50.00%
Performance Shares \| If Positive Absolute Total Shareholder Return, Achieved
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	7 years

The total fair value of shares issued during the period under a deferred compensation arrangement.

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-Publisher FASB
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-SubTopic 10
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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 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 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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Percentage of vesting of award under share-based payment arrangement.

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