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Represents the amount of reimbursement payable to related party if specified minimum common share price maintain during the one year period after the date on which the reimbursement is approved by shareholders.

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Represents the amount of reimbursement payable to related party if specified minimum common share price maintain during the one year period between the first and second anniversaries of the date on which the reimbursement is approved by shareholders.

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Related Party Reimbursement Amount Paid

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Share Price, During First and Second Year After Date

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Share Price, During One Year Period After Date

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- Definition

Area of a real estate property.

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No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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.

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No definition available.

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- Definition

Amount of unrealized gain (loss) recognized in the income statement for a financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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- Definition

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

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No definition available.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Fair Value of Assets and Liabilities - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) Tenant	Dec. 31, 2014 USD ($) ft² property	Jul. 31, 2014 USD ($) $ / shares	Mar. 31, 2014 ft²
Fair value of assets and liabilities
Impairment of Real Estate		$ 17,200
Number of properties \| property			31
Property square feet \| ft²			5,600,000		5,641,450
Real estate properties, net		$ 2,988,413	$ 4,697,998
Number of tenants responsible for more than 3% of total annualized rents \| Tenant		0
Total rents \| Credit concentration
Fair value of assets and liabilities
Concentration risk		4.00%
225 Water Street in Jacksonville, Florida
Fair value of assets and liabilities
Loss on asset impairment			22,700
Level 3 \| Real estate properties held for sale \| Discounted cash flows
Fair value of assets and liabilities
Fair value of assets			414,625
Carrying Amount \| Nonrecurring \| 225 Water Street in Jacksonville, Florida
Fair value of assets and liabilities
Real estate properties, net			42,300
Fair value \| Nonrecurring \| 225 Water Street in Jacksonville, Florida
Fair value of assets and liabilities
Fair value of assets			$ 19,600
Disposition Plan
Fair value of assets and liabilities
Number of properties \| property			34
Loss on asset impairment			$ 167,100
Disposition Plan \| Carrying Amount \| Nonrecurring
Fair value of assets and liabilities
Real estate properties, net			581,700
Previously reported
Fair value of assets and liabilities
Loss on asset impairment			4,800
General and administrative expense
Fair value of assets and liabilities
Change in fair value of derivatives		$ 9,000
Minimum
Fair value of assets and liabilities
Average closing price per common share during one year period after date (in dollars per share) \| $ / shares				$ 26.00
Average closing price per common share during first and second year after date (in dollars per share) \| $ / shares				$ 26.00
Related/Corvex
Fair value of assets and liabilities
Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period after the date on which the reimbursement is approved by shareholders				$ 8,400
Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period between the first and second anniversaries of the date on which the reimbursement is approved by shareholders				$ 8,400
Amount of reimbursements payable to related party upon the approval of shareholders	$ 8,400		$ 16,700