ACQUISITIONS - Schedule of Pro Forma Information (Details) - RPAI - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Rental income	$ 186,171	$ 369,515
Net loss	(31,891)	(48,765)
Net loss attributable to common shareholders	$ (31,535)	$ (48,215)
Net loss attributable to common shareholders per common share, basic (in USD per share)	$ (0.14)	$ (0.22)
Net loss attributable to common shareholders per common share, diluted (in USD per share)	$ (0.14)	$ (0.22)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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