REAL ESTATE AND ACQUIRED IN PLACE LEASE VALUE - Schedule of Investments in Consolidated Properties (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Real Estate [Abstract]
Land	$ 1,319.2	$ 1,277.6
Buildings	3,961.9	3,744.1
Building improvements	494.2	545.6
Acquired in-place lease values	295.0	330.6
Real estate investment, at cost	6,070.3	5,897.9
Less accumulated depreciation and amortization	(882.2)	(838.1)
Real estate and acquired in place lease values, net of accumulated depreciation and amortization	5,188.1	5,059.8
Buildings, Building Improvements and Acquired In-Place Lease Values
Real Estate Properties [Line Items]
Depreciation and amortization expense	$ 162.7	$ 151.3	$ 165.7
Building and Building Improvements \| Maximum
Real Estate Properties [Line Items]
Estimated useful life (in years)	40 years

Investment Buildings

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- Definition

Investment Buildings Improvements

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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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.

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