Operating Leases (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Property Subject to or Available for Operating Lease [Line Items]
Number of real estate properties owned or had a majority interest in	89us-gaap_NumberOfRealEstateProperties
Number of states in which entity has properties	13
Number of leases	2,700frt_NumberOfLeases
Percent of annualized base rent	3.10%frt_PercentOfAnnualizedBaseRentMaximum
Operating Leases, Future Minimum Payments Receivable [Abstract]
2015	484,911
2016	447,519
2017	389,507
2018	323,748
2019	268,600
Thereafter	1,718,254
Total	3,632,539
Retail and commercial \| Minimum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	3 years
Retail and commercial \| Maximum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	10 years
Residential \| Maximum
Property Subject to or Available for Operating Lease [Line Items]
Operating lease, term	1 year

Number Of Leases

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- Definition

Operating Lease, Term

+ References

No definition available.

+ Details

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- Definition

Percent of Annualized Base Rent Maximum

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

+ Details

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- Details

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the third year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the second year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

+ References

+ Details

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- Details

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- Details

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- Details

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