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[Line Items] for Business Acquisition, Pro Forma Information [Table]

No definition available.

Name:	reg_BusinessAcquisitionProFormaInformationLineItems
Namespace Prefix:	reg_
Data Type:	xbrli:stringItemType
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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Name:	us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Name:	us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

Name:	us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

Name:	us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

Name:	us-gaap_BusinessAcquisitionsProFormaRevenue
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Name:	us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463