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Commitments and Contingencies - Narrative (Details) | Mar. 31, 2019 USD ($) Property | Aug. 31, 2010 USD ($)
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Environmental Indemnity Agreement |  |
Number of properties which were provided environmental indemnifications | Property | 3 |
Maximum additional costs agreed to be paid by the entity under environmental indemnification agreement | $ 19,000,000 |
Development and Redevelopment Obligations |  |
Environmental Indemnity Agreement |  |
Purchase obligations | 184,300,000 |
Tenant and Other Capital Improvements |  |
Environmental Indemnity Agreement |  |
Purchase obligations | 45,300,000 |
Third Party Construction |  |
Environmental Indemnity Agreement |  |
Purchase obligations | 32,600,000 |
Other Obligations |  |
Environmental Indemnity Agreement |  |
Purchase obligations | $ 1,700,000 |
Specialty Tax Guarantee | Anne Arundel County, Maryland | Tax Incremental Financing Bond |  |
Environmental Indemnity Agreement |  |
Loan amount |  | $ 30,000,000

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