SEGMENT REPORTING - Operating Activity Within Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Segment profit	$ 30,384	$ 27,275	$ 83,692	$ 57,444
Total segments’ profit	63,431	52,337	171,920	159,616
Retail
Segment Reporting Information [Line Items]
Property revenue	25,848	25,925	81,156	78,497
Property expense	(7,806)	(7,062)	(22,691)	(21,011)
Segment profit	18,042	18,863	58,465	57,486
Office
Segment Reporting Information [Line Items]
Property revenue	42,810	27,251	100,816	85,073
Property expense	(11,627)	(8,243)	(29,385)	(24,598)
Segment profit	31,183	19,008	71,431	60,475
Multifamily
Segment Reporting Information [Line Items]
Property revenue	12,655	12,848	38,451	37,894
Property expense	(5,367)	(5,157)	(15,323)	(15,174)
Segment profit	7,288	7,691	23,128	22,720
Mixed-use
Segment Reporting Information [Line Items]
Property revenue	17,049	16,483	47,371	46,798
Property expense	(10,131)	(9,708)	(28,475)	(27,863)
Segment profit	$ 6,918	$ 6,775	$ 18,896	$ 18,935

Property expenses.

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

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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.

+ References

No definition available.

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