Real Estate Properties - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) ft² lease building joint_venture
Real Estate Properties [Line Items]
Number of joint ventures \| joint_venture	2
Number of leases entered \| lease	32
Rentable square feet (in sqft) \| ft²	825,475
Weighted average lease term	7 years 6 months
Expenditures committed on leases \| $	$ 28,804
Committed but unspent tenant related obligations estimated \| $	$ 63,580
Continuing operations
Real Estate Properties [Line Items]
Number of buildings \| building	212
Rentable area of properties (in square feet) \| ft²	30,134,000
Carry value of properties \| $	$ 3,955,529
Unconsolidated Joint Ventures
Real Estate Properties [Line Items]
Number of buildings \| building	3
Rentable area of properties (in square feet) \| ft²	443,900
Number of buildings, noncontrolling interest \| building	3
Joint Venture 1
Real Estate Properties [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Joint Venture 2
Real Estate Properties [Line Items]
Equity Method Investment, Ownership Percentage	51.00%

Noncontrolling Interest, Number Of Buildings

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- Definition

The number of buildings owned as of the balance sheet date.

+ References

No definition available.

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- Definition

Number Of Joint Ventures

+ References

No definition available.

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- Definition

Represents number of leases executed during the reporting period.

+ References

No definition available.

+ Details

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- Definition

Represents committed expenditures for operating leases executed during the period.

+ References

No definition available.

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- Definition

Represents the area of leased property related to operating leases executed during the period.

+ References

No definition available.

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- Definition

Represents committed but unspent tenant related obligations based on executed operating leases as of the balance sheet date.

+ References

No definition available.

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- Definition

Represents the weighted average lease term of operating leases.

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

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.

+ References

No definition available.

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