Amount of liability recognized arising from contingent consideration in a business combination.

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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 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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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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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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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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Share-Based Payments and Employee Benefits - OP Units (Details) - OP Units - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Jul. 18, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Equity grants (in shares)	3,300,000
Estimated grant-date fair value	$ 110.6
Unvested Shares
Beginning balance		2,872,252
Vested		(1,351,682)
Ending balance		1,520,570	2,872,252
Weighted Average Grant-Date Fair Value
Beginning balance		$ 33.39
Vested (in dollars per share)		33.39
Ending balance		$ 33.39	$ 33.39
Total-grant date fair value for vested awards		$ 45.1	$ 4.3	$ 3.2
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting over period	12 months
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting over period	60 months