Concentration Risk, Number Of Properties Occupied

No definition available.

Name:	cmct_ConcentrationRiskNumberOfPropertiesOccupied
Namespace Prefix:	cmct_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of states in which the entity owns real estate properties as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	cmct_NumberofStatesinwhichRealEstatePropertiesareOwned
Namespace Prefix:	cmct_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(5))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_ConcentrationRiskLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

CONCENTRATIONS (Details) $ in Thousands	12 Months Ended
CONCENTRATIONS (Details) $ in Thousands	Dec. 31, 2019 USD ($) property state	Dec. 31, 2018 USD ($) property	Dec. 31, 2017 property
Concentrations
Number of states in which properties are owned \| state	2
Office properties
Concentrations
Number of real estate properties owned	8	16	15
Hotel properties
Concentrations
Number of real estate properties owned	1	1	1
Parking garages
Concentrations
Number of real estate properties owned	1	2	2
Development site
Concentrations
Number of real estate properties owned	1	2	2
Parking lot
Concentrations
Number of real estate properties owned	1	1	1
Kaiser Foundation Health Plan, Inc.
Concentrations
Number of properties occupied	2
Revenues \| Tenant revenue concentrations \| Kaiser Foundation Health Plan, Inc.
Concentrations
Concentration risk, percent	17.30%	12.90%	10.80%
Accounts receivable \| $	$ 23	$ 331
Revenues \| Tenant revenue concentrations \| Governmental Tenants
Concentrations
Concentration risk, percent	17.10%	24.60%	29.40%
Accounts receivable \| $	$ 282	$ 2,899
Revenues \| Geographical concentrations
Concentrations
Concentration risk, percent	100.00%	100.00%	100.00%
Revenues \| Geographical concentrations \| California
Concentrations
Concentration risk, percent	80.60%	76.00%	63.30%
Revenues \| Geographical concentrations \| Texas
Concentrations
Concentration risk, percent	5.50%	3.30%	6.90%
Revenues \| Geographical concentrations \| Washington, D.C.
Concentrations
Concentration risk, percent	13.90%	20.70%	25.10%
Revenues \| Geographical concentrations \| North Carolina
Concentrations
Concentration risk, percent	0.00%	0.00%	3.10%
Revenues \| Geographical concentrations \| New York
Concentrations
Concentration risk, percent	0.00%	0.00%	1.60%
Real estate investments \| Geographical concentrations
Concentrations
Concentration risk, percent	100.00%	100.00%
Real estate investments \| Geographical concentrations \| California
Concentrations
Concentration risk, percent	94.40%	70.60%
Real estate investments \| Geographical concentrations \| Texas
Concentrations
Concentration risk, percent	5.60%	2.20%
Real estate investments \| Geographical concentrations \| Washington, D.C.
Concentrations
Concentration risk, percent	0.00%	27.20%