XML 67 R50.htm IDEA: XBRL DOCUMENT
v3.19.3

Real Estate - Real Estate Under Development and Construction in Progress - Additional Information (Details) - property | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Property, Plant and Equipment [Line Items] |  |  |
Number of projects put into service during period | 1 |  |
Number of unconsolidated project in development |  |  | 1
Core Portfolio |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Number of projects put into service during period |  | 1 |

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- Definition Number of real estate projects put into service during period. + References No definition available. + Details
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Namespace Prefix: | akr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- Definition Number of unconsolidated real estate project in development. + References No definition available. + Details
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Namespace Prefix: | akr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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

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- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=akr_CorePortfolioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |