Line of credit facility extension allowed period.

No definition available.

Name:	cdr_LineOfCreditFacilityExtensionAllowedPeriod
Namespace Prefix:	cdr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The expiration, mandatory redemption, or due date, month and year (YYYY-MM), of the financial instrument issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

+ Details

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

- Definition

Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

+ References

+ Details

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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

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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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- Details

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Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Mortgage Loans Payable and Credit Facility (Schedule of Debt and Capital Lease Obligations Related to Continuing Operations) (Parenthetical) (Details)			3 Months Ended
	Apr. 01, 2019	Sep. 08, 2017	Mar. 31, 2019
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate			1.35%
Line of credit facility extension allowed period		1 year	1 year
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate		1.35%
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate		1.95%
Revolving Credit Facility [Member] \| Unsecured credit facility [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate	0.14%
Revolving Credit Facility [Member] \| Unsecured credit facility [Member] \| Minimum [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate	0.10%
Revolving Credit Facility [Member] \| Unsecured credit facility [Member] \| Maximum [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Basis spread on borrowings variable rate	0.15%
Term Loan Six [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Expiration period			2020-02
Effective interest rate			3.20%