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Commitments and Contingencies - Narrative (Details) | Sep. 30, 2016 USD ($) Property | Aug. 31, 2010 USD ($)
--- | --- | ---
Tax incremental financing obligation |  |
Liability recognized with regard to tax incremental financing obligation at end of current period | $ 1,300,000 |
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 |
New Development and Redevelopment Obligations |  |
Loss Contingencies [Line Items] |  |
Purchase obligations | 77,600,000 |
Capital Expenditures For Operating Properties |  |
Loss Contingencies [Line Items] |  |
Purchase obligations | 60,500,000 |
Third Party Construction and Development |  |
Loss Contingencies [Line Items] |  |
Purchase obligations | 10,500,000 |
Other Purchase Obligations |  |
Loss Contingencies [Line Items] |  |
Purchase obligations | $ 1,800,000 |
Anne Arundel County, Maryland | Tax Incremental Financing Bond |  |
Tax incremental financing obligation |  |
Debt instrument, face amount |  | $ 30,000,000

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