Amount of real estate taxes and insurance attributable to disposal group, but not limited to, discontinued operation.

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Represents the number of office properties sold.

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Area of a real estate property.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount after tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until disposal.

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Amount of depreciation and amortization expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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No definition available.

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The cash inflow from the sale of formerly productive land held for sale, anything permanently fixed to it, including buildings, structures on it, and so forth.

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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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Disposition of Properties (Details)						2 Months Ended	3 Months Ended		9 Months Ended
Disposition of Properties (Details)	Oct. 26, 2023 USD ($) property	Aug. 09, 2023 USD ($) property	Mar. 10, 2023 USD ($) property	Dec. 28, 2022 USD ($)	Aug. 31, 2022 USD ($) property	Dec. 31, 2023 USD ($) property	Sep. 30, 2023 USD ($) ft²	Sep. 30, 2022 USD ($) ft²	Sep. 30, 2023 USD ($) ft²	Sep. 30, 2022 USD ($) ft²	Dec. 31, 2022 USD ($)
Dispositions of properties
Number of properties sold \| property	1
Assets Held-for-sale, Not Part of Disposal Group							$ 132,659,000		$ 132,659,000
Sale price	$ 46,700,000
Area of property (in square feet) \| ft²							6,206,460	6,433,954	6,206,460	6,433,954
Real estate assets							$ 921,581,000		$ 921,581,000		$ 1,103,248,000
Straight-line rent receivable							43,253,000		43,253,000		52,739,000
Deferred leasing commissions							25,226,000		25,226,000		35,709,000
Acquired real estate leases							7,447,000		7,447,000		$ 10,186,000
Operating results for discontinued operations:
Rental revenue							5,354,000	$ 8,592,000	16,062,000	$ 27,646,000
Rental operating expenses							(1,862,000)	(2,809,000)	(5,277,000)	(8,669,000)
Real estate taxes and insurance							(720,000)	(2,416,000)	(2,264,000)	(7,287,000)
Depreciation and amortization							(1,034,000)	(3,157,000)	(5,372,000)	(10,246,000)
Income from dispositions and assets held for sale							1,738,000	$ 210,000	3,149,000	$ 1,444,000
Office properties in Broomfield, Colorado
Dispositions of properties
Number of properties sold \| property					2
Gain (loss) on sale of property					$ 24,100,000
Sale price					$ 102,500,000
Property in Atlanta, Georgia
Dispositions of properties
Gain (loss) on sale of property							(20,500,000)
Sale price							40,000,000.0
Office Property in Evanston, Illinois
Dispositions of properties
Gain (loss) on sale of property				$ 3,900,000
Sale price				$ 27,800,000
Property in Plano, Texas
Dispositions of properties
Assets Held-for-sale, Not Part of Disposal Group							36,200,000		36,200,000
Gain (loss) on sale of property							10,600,000
Sale price							48,000,000.0
Real estate assets							32,600,000		32,600,000
Straight-line rent receivable							1,400,000		1,400,000
Deferred leasing commissions							1,700,000		1,700,000
Acquired real estate leases							500,000		$ 500,000
Property in Plano, Texas \| Subsequent event
Dispositions of properties
Gain (loss) on sale of property	10,600,000
Sale price	$ 48,000,000.0
Office Property in Charlotte, North Carolina
Dispositions of properties
Number of properties sold \| property		1
Gain (loss) on sale of property		$ (800,000)
Sale price		$ 9,200,000
Office Property in Elk Grove Village, Illinois
Dispositions of properties
Number of properties sold \| property			1
Gain (loss) on sale of property			$ 8,400,000
Sale price			$ 29,100,000
Property in Addison, Texas
Dispositions of properties
Gain (loss) on sale of property							$ 53,000
Area of property (in square feet) \| ft²							7,826		7,826
Property in Miami, Florida
Dispositions of properties
Gain (loss) on sale of property							$ (19,200,000)
Sale price							68,000,000.0
Properties in Miami, Florida and Atlanta, Georgia
Dispositions of properties
Assets Held-for-sale, Not Part of Disposal Group							96,400,000		$ 96,400,000
Real estate assets							122,200,000		122,200,000
Straight-line rent receivable							5,500,000		5,500,000
Deferred leasing commissions							$ 8,400,000		8,400,000
Impairment charge									$ 39,700,000
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Dispositions of properties
Number of properties sold \| property						2
Sale price						$ 96,500,000