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

Weighted average number of operating partnership units outstanding.

No definition available.

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

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.

No definition available.

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

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.

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 https://asc.fasb.org/extlink&oid=126958026&loc=SL5498026-109256

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

Number of options outstanding, including both vested and non-vested options.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Number of shares issued under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901