Acquired Ground Leases, Weighted Average Useful Life

No definition available.

Name:	fce_AcquiredGroundLeasesWeightedAverageUsefulLife
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- Definition

Company's equity ownership exchanged

+ References

No definition available.

+ Details

Name:	fce_Companysequityownershipexchanged
Namespace Prefix:	fce_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Gain on change in control of interests, tax

+ References

No definition available.

+ Details

Name:	fce_Gainonchangeincontrolofintereststax
Namespace Prefix:	fce_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

[Line Items] for Net Gain on Change in Control of Interest [Table]

+ References

No definition available.

+ Details

Name:	fce_NetGainonChangeinControlofInterestLineItems
Namespace Prefix:	fce_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net proceeds to finance acquisition

+ References

No definition available.

+ Details

Name:	fce_Netproceedstofinanceacquisition
Namespace Prefix:	fce_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of parking facilities

+ References

No definition available.

+ Details

Name:	fce_Numberofparkingfacilities
Namespace Prefix:	fce_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of properties acquired

+ References

No definition available.

+ Details

Name:	fce_Numberofpropertiesacquired
Namespace Prefix:	fce_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of properties exchanged

+ References

No definition available.

+ Details

Name:	fce_Numberofpropertiesexchanged
Namespace Prefix:	fce_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

+ Details

Name:	us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

+ References

No definition available.

+ Details

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

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationStepAcquisitionEquityInterestInAcquireeIncludingSubsequentAcquisitionPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

+ Details

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

- Definition

Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

+ Details

Name:	us-gaap_FairValueInputsDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the amount of value allocated by a lessor (acquirer) to lease agreements which exist at acquisition of a leased property. Such amount may include the value assigned to existing tenant relationships and excludes the market adjustment component of the value assigned for above or below-market leases acquired.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetAcquiredInPlaceLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Net long-term land leases which are capitalized as part of real property.

+ References

No definition available.

+ Details

Name:	us-gaap_GroundLeasesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=fce_UniversityParkatMITMember
Namespace Prefix:
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- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_LeasesAcquiredInPlaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=fce_BelowmarkettenantleasesMember
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Data Type:	na
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- Details

Name:	us-gaap_LeaseArrangementTypeAxis=fce_BelowmarketgroundleasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=fce_AbovemarketgroundleasesMember
Namespace Prefix:
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- Details

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- Details

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Net Gain on Change in Control of Interests (Details Textuals)	1 Months Ended	3 Months Ended		6 Months Ended	9 Months Ended
	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2015 properties	Apr. 30, 2015 properties
Net Gain on Change in Control of Interest [Line Items]
Net gain on change in control of interests		$ 0	$ 0		$ 487,684,000	$ 2,759,000
University Park at MIT [Member]
Net Gain on Change in Control of Interest [Line Items]
Partner's equity ownership acquired	49.00%			49.00%
Number of properties acquired \| properties								7
Company's ownership interest after acquisition	100.00%	100.00%		100.00%	100.00%
Number of parking facilities	2			2				2
Ownership percentage prior to sale	51.00%	51.00%		51.00%	51.00%
In-place leases							$ 78,000,000
Below market tenant leases							49,000,000
Weighted-average discount rate applied to cash flows	7.00%
Weighted-average terminal capitalization rate	6.00%
Net gain on change in control of interests				$ 463,643,000	$ 463,643,000
Gain on change in control of interests, tax					$ 179,815,000
University Park at MIT [Member] \| Above Market Leases [Member]
Net Gain on Change in Control of Interest [Line Items]
Weighted average life	3 years 7 months
University Park at MIT [Member] \| Below-market tenant leases [Member]
Net Gain on Change in Control of Interest [Line Items]
Weighted average life	3 years 7 months
University Park at MIT [Member] \| Below-market ground leases [Member]
Net Gain on Change in Control of Interest [Line Items]
Ground leases							20,000,000
Acquired ground leases, weighted average life	60 years
University Park at MIT [Member] \| Above-market ground leases [Member]
Net Gain on Change in Control of Interest [Line Items]
Ground leases							$ 24,000,000
Acquired ground leases, weighted average life	58 years
University Park at MIT [Member] \| May 2015 Common Stock Issuance [Member]
Net Gain on Change in Control of Interest [Line Items]
Net proceeds to finance acquisition	$ 386,156,000
Apartment Communities transaction [Member]
Net Gain on Change in Control of Interest [Line Items]
Partner's equity ownership acquired									50.00%
Number of properties acquired \| properties									3
Company's equity ownership exchanged									50.00%
Number of properties exchanged \| properties									5
Company's ownership interest after acquisition									100.00%