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Investment in Real Estate - Additional Information (Details) ft² in Thousands | Mar. 31, 2022 ft² Property
--- | ---
Real Estate Properties [Line Items] |
Number of industrial properties | 414
Gross leasable area (GLA) of industrial properties | ft² | 62,300
Acquisition Activity |
Real Estate Properties [Line Items] |
Number of industrial properties | 2
Gross leasable area (GLA) of industrial properties | ft² | 40
Number of Land Parcels | 5

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- Definition Number of Land Parcels + References No definition available. + Details
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Namespace Prefix: | fr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Area of a real estate property. + References No definition available. + Details
Name: | us-gaap_AreaOfRealEstateProperty
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:areaItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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

X
- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |