The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The aggregate costs of keeping the property in good condition but that do not appreciably prolong the life or increase the value of the property.

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For an unclassified balance sheet, the accumulated amortization, as of the reporting date, which represents the periodic charge to earnings of initial direct costs which have been deferred and are being allocated over the lease term in proportion to the recognition of rental income.

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This element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This element is net of accumulated amortization.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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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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Real Estate Transactions - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Real Estate [Line Items]
Right-of-use asset	$ 3,700,000
Operating lease liability	3,700,000
Deferred leasing costs, net	23,420,000		$ 24,005,000
Accumulated amortization deferred leasing cost	49,300,000		$ 48,700,000
Depreciation expense	11,200,000	$ 11,500,000
Repairs and maintenance expense	4,500,000	3,900,000
Impairment of real estate	$ 0
Minimum
Real Estate [Line Items]
Operating lease term of contract	1 year
Maximum
Real Estate [Line Items]
Operating lease term of contract	15 years
Building \| Minimum
Real Estate [Line Items]
Estimated useful life	35 years
Building \| Maximum
Real Estate [Line Items]
Estimated useful life	50 years
Building Improvements \| Maximum
Real Estate [Line Items]
Estimated useful life	20 years
Lease Acquisition Costs
Real Estate [Line Items]
Amortization of intangible assets	$ 1,100,000	$ 1,200,000