Prepaid Expenses and Other Assets, Net (Details) - USD ($) $ in Thousands |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|
| Property, Plant and Equipment [Line Items] | ||||
| Restricted cash | $ 3,884 | $ 2,570 | $ 2,756 | $ 1,953 |
| Marketable securities in deferred compensation plan | 3,868 | 4,616 | ||
| Total for COPT and subsidiaries | 85,581 | 71,334 | ||
| Corporate Office Properties, L.P. [Member] | ||||
| Property, Plant and Equipment [Line Items] | ||||
| Prepaid expenses | 25,658 | 24,670 | ||
| Lease incentives, net | 21,258 | 19,011 | ||
| Furniture, fixtures and equipment, net | 8,630 | 5,256 | ||
| Non-real estate equity investments | 5,940 | 5,056 | ||
| Deferred financing costs, net | 4,733 | 1,202 | ||
| Restricted cash | 3,884 | 2,570 | $ 2,756 | $ 1,953 |
| Construction contract costs incurred in excess of billings | 3,189 | 4,884 | ||
| Deferred tax asset, net | 2,084 | 1,892 | ||
| Other assets | 6,337 | 2,177 | ||
| Total for COPT and subsidiaries | $ 81,713 | $ 66,718 |
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- Definition Deferred Financing and Derivative Costs, Net No definition available.
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- Definition This item represents the carrying amount on the entity's balance sheet of cost method and equity method investments in investees whose primary activities are unrelated to real estate. No definition available.
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- Definition Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This item represents the deferred charge for an incentive or inducement granted by a lessor to a lessee, in order to motivate the lessee to enter the lease agreement, which incentive or inducement is to be recognized as a reduction of rental revenue over the lease term. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of assets classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets. No definition available.
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- Definition Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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