Future Rental Revenues - Minimum Lease Payments Receivable, Excluding Tenant Reimbursements of Expenses, Under Non-Cancelable Operating Leases (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Disclosure Future Rental Revenues Minimum Lease Payments Receivable Excluding Tenant Reimbursements Of Expenses Under Non Cancelable Operating Leases [Abstract]
2014	$ 242,261
2015	210,117
2016	167,903
2017	134,636
2018	102,717
Thereafter	298,738
Total	$ 1,156,372

Name:	fr_DisclosureFutureRentalRevenuesMinimumLeasePaymentsReceivableExcludingTenantReimbursementsOfExpensesUnderNonCancelableOperatingLeasesAbstract
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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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- 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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