Estimated Liability Upon Exercise Of Option

No definition available.

Name:	frt_EstimatedLiabilityUponExerciseOfOption
Namespace Prefix:	frt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of Members With Purchase Options

+ References

No definition available.

+ Details

Name:	frt_NumberOfMembersWithPurchaseOptions
Namespace Prefix:	frt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Fair value of operating partnership units at the balance sheet date.

+ References

No definition available.

+ Details

Name:	frt_OperatingPartnershipUnitsFairValue
Namespace Prefix:	frt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Option Indexed to Issuer's Equity, Percentage Of Indexed Ownership Interest

+ References

No definition available.

+ Details

Name:	frt_OptionIndexedToIssuersEquityPercentageOfIndexedOwnershipInterest
Namespace Prefix:	frt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of partnership interest we are required to purchase in a put option.

+ References

No definition available.

+ Details

Name:	frt_OwnershipInterestOfOtherPartnerInPutOption
Namespace Prefix:	frt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Purchase Price Under Option

+ References

No definition available.

+ Details

Name:	frt_PurchasePriceUnderOption
Namespace Prefix:	frt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(a))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 5

-Subparagraph (SAB TOPIC 4.F)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 16

-Subparagraph a, b

-Article 6

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-04.16(b))

-URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996

+ Details

Name:	us-gaap_PartnersCapitalAccountUnits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(5))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

Name:	us-gaap_ProductWarrantyAccrual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

Name:	us-gaap_ProductWarrantyAccrualPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	frt_ContractualObligationAxis=frt_CapitalImprovementDevelopmentAndRedevelopmentProjectsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=frt_MemberOneInPlazaElSegundoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CounterpartyNameAxis=frt_MemberTwoInPlazaElSegundoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=frt_CongressionalPlazaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=frt_MontroseCrossingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=frt_PlazaElSegundoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RealEstatePropertiesAxis=frt_ProjectInSouthernCaliforniaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Commitments and Contingencies (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2023	Sep. 30, 2025	Jan. 01, 2017	Oct. 16, 2023	Oct. 16, 2021
Loss Contingencies [Line Items]
Reserves for warranties and general liability	$ 7.2us-gaap_ProductWarrantyAccrual	$ 7.4us-gaap_ProductWarrantyAccrual
Payments from reserves	1.4us-gaap_ProductWarrantyAccrualPayments	1.2us-gaap_ProductWarrantyAccrualPayments
Letters of credit outstanding, amount	13.0
Operating partnership units, outstanding	917,255us-gaap_PartnersCapitalAccountUnits
Operating partnership units outstanding, fair value	122.4frt_OperatingPartnershipUnitsFairValue
Congressional Plaza \| Put Option
Loss Contingencies [Line Items]
Maximum partnership percentage required to purchase	100.00%
Indexed ownership interest percentage	29.47%
Congressional Plaza \| Put Option \| Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	72
Congressional Plaza \| Put Option \| Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	76
Project In Southern California \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.00%
Montrose Crossing \| Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	9
Montrose Crossing \| Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	10
Montrose Crossing \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.10%
Plaza El Segundo \| Minimum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	18
Plaza El Segundo \| Maximum
Loss Contingencies [Line Items]
Estimated maximum liability upon exercise of the put option	21
Plaza El Segundo \| Put Option
Loss Contingencies [Line Items]
Number of members with purchase options	2
Scenario, Forecast \| Mercer Mall
Loss Contingencies [Line Items]
Purchase price under option			55.0
Scenario, Forecast \| Mercer Mall \| Put Option
Loss Contingencies [Line Items]
Purchase price under option				60.0
Scenario, Forecast \| Plaza El Segundo \| Maximum
Loss Contingencies [Line Items]
Purchase price under option					4.9
Scenario, Forecast \| The Grove at Shrewsbury \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage					4.80%
Scenario, Forecast \| Brook 35 \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage					8.80%
Scenario, Forecast \| Melville Mall
Loss Contingencies [Line Items]
Purchase price under option						5.0	5.0
Capital improvement, development, and redevelopment projects
Loss Contingencies [Line Items]
Contractual obligations	$ 232.3
Member One In Plaza El Segundo \| Plaza El Segundo \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	10.00%
Member Two In Plaza El Segundo \| Plaza El Segundo \| Put Option
Loss Contingencies [Line Items]
Indexed ownership interest percentage	11.80%