For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - CONCENTRATION OF CREDIT RISK (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment square footage \| Geographic Concentration Risk \| Income Properties \| Florida
CONCENTRATION OF CREDIT RISK
Concentration risk percentage	24.00%
Consolidated revenues \| Office Properties \| Hillsboro, Oregon and Raleigh, North Caroline
CONCENTRATION OF CREDIT RISK
Concentration risk percentage	12.50%	13.50%	15.30%