Contingencies - Guarantees (Details)	9 Months Ended
Sep. 30, 2020 USD ($) extension_option	Dec. 31, 2019 USD ($)
Guarantor Obligations [Line Items]
Obligation Recorded to Reflect Guaranty	$ 962,000	$ 973,000
Shoppes at Eagle Point, LLC
Guarantor Obligations [Line Items]
Maximum Guaranteed Amount	$ 12,740,000
Parkdale Self Storage LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Debt Instrument, Face Amount	$ 6,500,000
Partnership guarantee (as a percent)	100.00%
Hamilton Place Self Storage, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	54.00%
Reduction of guarantor obligations once certain debt and operational metrics are met (as a percent)	25.00%
Debt Instrument, Face Amount	$ 7,002,000
Partnership guarantee (as a percent)	100.00%
Reduction of guarantor obligations upon opening (as a percent)	50.00%
Ambassador Infrastructure, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	65.00%
Outstanding Balance	$ 9,360,000
Percentage Guaranteed by the Operating Partnership (as a percent)	100.00%
Maximum Guaranteed Amount	$ 9,360,000
Obligation Recorded to Reflect Guaranty	$ 94,000	101,000
Hamilton Place Self Storage, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	54.00%
Outstanding Balance	$ 6,247,000
Percentage Guaranteed by the Operating Partnership (as a percent)	100.00%
Maximum Guaranteed Amount	$ 7,002,000
Obligation Recorded to Reflect Guaranty	$ 70,000	70,000
West Melbourne I, LLC - Phase I
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 40,372,000
Percentage Guaranteed by the Operating Partnership (as a percent)	50.00%
Maximum Guaranteed Amount	$ 20,186,000
Obligation Recorded to Reflect Guaranty	$ 202,000	199,000
West Melbourne I, LLC - Phase II
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 14,513,000
Percentage Guaranteed by the Operating Partnership (as a percent)	50.00%
Maximum Guaranteed Amount	$ 7,257,000
Obligation Recorded to Reflect Guaranty	$ 73,000	78,000
Port Orange I, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 53,513,000
Percentage Guaranteed by the Operating Partnership (as a percent)	50.00%
Maximum Guaranteed Amount	$ 26,757,000
Obligation Recorded to Reflect Guaranty	$ 268,000	270,000
Shoppes at Eagle Point, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 35,189,000
Percentage Guaranteed by the Operating Partnership (as a percent)	35.00%
Maximum Guaranteed Amount	$ 12,740,000
Obligation Recorded to Reflect Guaranty	$ 127,000	127,000
Number of extension options available \| extension_option	1
Option extension term of debt instrument	1 year
EastGate Storage, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 6,485,000
Percentage Guaranteed by the Operating Partnership (as a percent)	50.00%
Maximum Guaranteed Amount	$ 3,250,000
Obligation Recorded to Reflect Guaranty	$ 33,000	33,000
Reduction of guarantor obligations once certain debt and operational metrics are met (as a percent)	25.00%
Self-Storage at Mid Rivers, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 5,853,000
Percentage Guaranteed by the Operating Partnership (as a percent)	50.00%
Maximum Guaranteed Amount	$ 2,994,000
Obligation Recorded to Reflect Guaranty	$ 30,000	30,000
Reduction of guarantor obligations once certain debt and operational metrics are met (as a percent)	25.00%
Reduction of guarantor obligations once construction is complete (as a percent)	25.00%
Parkdale Self Storage LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 6,065,000
Percentage Guaranteed by the Operating Partnership (as a percent)	100.00%
Maximum Guaranteed Amount	$ 6,500,000
Obligation Recorded to Reflect Guaranty	$ 65,000	$ 65,000
Atlanta Outlet Outparcels, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 4,632,000
Percentage Guaranteed by the Operating Partnership (as a percent)	100.00%
Maximum Guaranteed Amount	$ 4,632,000
Louisville Outlet Shoppes, LLC
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Outstanding Balance	$ 9,122,000
Percentage Guaranteed by the Operating Partnership (as a percent)	100.00%
Maximum Guaranteed Amount	$ 9,122,000
West Melbourne I LLC Phase I, West Melbourne I LLC Phase II and Port Orange I, LLC
Guarantor Obligations [Line Items]
Number of extension options available \| extension_option	2
Option extension term of debt instrument	1 year
York Town Center Lp
Guarantor Obligations [Line Items]
Company's Ownership Interest (as a percent)	50.00%
Undiscounted maximum exposure	$ 22,000,000
Annual reductions to guarantors obligations	800,000
Guaranteed minimum exposure amount	10,000,000
Guaranteed amount of the outstanding loan based on percentage	$ 11,600,000
Guarantor obligations recoverable (as a percent)	50.00%

The annual reduction amount to the Guarantor's Obligations.

No definition available.

Name:	cbl_AnnualReductionsToGuarantorsObligations
Namespace Prefix:	cbl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Percentage Guaranteed

+ References

No definition available.

+ Details

Name:	cbl_DebtInstrumentPercentageGuaranteed
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Period of Extension Option

+ References

No definition available.

+ Details

Name:	cbl_DebtInstrumentPeriodofExtensionOption
Namespace Prefix:	cbl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Portion of the loan amount guaranteed by the company based on the guaranty percentage.

+ References

No definition available.

+ Details

Name:	cbl_GuaranteedAmountOfOutstandingLoanBasedOnPercentage
Namespace Prefix:	cbl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Minimum potential amount of future payments (undiscounted) the company could be required to make under the guarantee or each group of similar guarantees after reductions.

+ References

No definition available.

+ Details

Name:	cbl_GuaranteedMinimumExposureAmount
Namespace Prefix:	cbl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Guarantor Obligations, Guaranty Reduction Percentage, Once Certain Debt and Operational Metrics Are Met

+ References

No definition available.

+ Details

Name:	cbl_GuarantorObligationsGuarantyReductionPercentageOnceCertainDebtAndOperationalMetricsAreMet
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Guarantor Obligations, Guaranty Reduction, Percentage, Once Construction Is Complete

+ References

No definition available.

+ Details

Name:	cbl_GuarantorObligationsGuarantyReductionPercentageOnceConstructionIsComplete
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Guarantor obligations guaranty reduction percentage upon opening.

+ References

No definition available.

+ Details

Name:	cbl_GuarantorObligationsGuarantyReductionPercentageUponOpening
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of third party construction loan guaranteed by the company.

+ References

No definition available.

+ Details

Name:	cbl_GuarantorObligationsPercentageObligationOfConstructionLoan
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents amount recoverable by guarantor from third parties for amounts paid under the guaranty.

+ References

No definition available.

+ Details

Name:	cbl_GuarantorObligationsRecoverable
Namespace Prefix:	cbl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Company's maximum guaranteed amount after loans were partially paid down.

+ References

No definition available.

+ Details

Name:	cbl_MaximumGuaranteeObligationAfterLoansPartiallyPaidDown
Namespace Prefix:	cbl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue From Contracts With Customers, Operating Agreements, Number Of Extension Options Available.

+ References

No definition available.

+ Details

Name:	cbl_RevenueFromContractsWithCustomersOperatingAgreementsNumberOfExtensionOptionsAvailable
Namespace Prefix:	cbl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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_GuaranteeObligationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

+ Details

Name:	us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12201-110248

+ Details

Name:	us-gaap_GuaranteesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents the current and noncurrent portions of a long-term real estate loan with an initial maturity beyond one year or beyond the normal operating cycle, if longer, to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project (generally one to seven years), usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_LongtermConstructionLoanCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=cbl_ShoppesAtEaglePointLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=cbl_ParkdaleSelfStorageLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=cbl_HamiltonPlaceSelfStorageLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=cbl_AmbassadorInfrastructureLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=cbl_HamiltonPlaceSelfStorageLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_WestMelbourneILLCPhaseIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_WestMelbourneILLCPhaseIIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_PortOrangeILlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_ShoppesAtEaglePointLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_EastGateStorageLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_SelfStorageAtMidRiversLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_ParkdaleSelfStorageLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_AtlantaOutletOutparcelsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_LouisvilleOutletShoppesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_WestMelbourneILLCPhaseIAndIIAndPortOrangeILLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=cbl_YorkTownCenterLpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: