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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- Definition

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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- Definition

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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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 ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Real Estate [Line Items]
Deferred leasing costs, net	$ 27,546		$ 24,083
Accumulated amortization deferred leasing cost	42,500		$ 41,600
Depreciation expense	10,000	$ 10,000
Repairs and maintenance expense	$ 2,800	3,700
Building \| Minimum
Real Estate [Line Items]
Estimated useful life (in years)	35 years
Building \| Maximum
Real Estate [Line Items]
Estimated useful life (in years)	50 years
Building Improvements \| Maximum
Real Estate [Line Items]
Estimated useful life (in years)	20 years
Lease Acquisition Costs
Real Estate [Line Items]
Amortization of intangible assets	$ 1,300	$ 1,600