Earnings Per Share (Narrative) (Details) - shares	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average nonvested restricted shares outstanding	400,000	500,000
Weighted average number of OP units outstanding	81,000	81,000
Market Performance-Based Equity Award [Member] \| Chief Executive Officer [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares issuable under Stock incentive plan	0	0

Share based compensation arrangement by share based payment award equity instruments other than options issuable during period.

No definition available.

+ Details

Name:	cdr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsIssuableDuringPeriod
Namespace Prefix:	cdr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average number of operating partnership units outstanding.

+ References

No definition available.

+ Details

Name:	cdr_WeightedAverageNumberOfOperatingPartnershipUnitsOutstanding
Namespace Prefix:	cdr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

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

- Definition

This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 68B
-URI http://asc.fasb.org/extlink&oid=125511455&loc=SL5498026-109256

+ Details

Name:	us-gaap_IncrementalCommonSharesAttributableToParticipatingNonvestedSharesWithNonForfeitableDividendRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=cdr_MarketPerformanceBasedEquityAwardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_TitleOfIndividualAxis=srt_ChiefExecutiveOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: