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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Dec. 31, 2018
Loss Contingencies [Line Items] |  |
Loss Contingency Accrual | $ 8.6 | $ 8.7
Cleven Litigation Case [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Estimate of Possible Loss | 54.6 |
Brown Litigation Case [Member] |  |
Loss Contingencies [Line Items] |  |
Loss Contingency, Estimate of Possible Loss | $ 8.4 |
Apartment Communities [Member] |  |
Loss Contingencies [Line Items] |  |
Lease expiration year | 2074 |
Office Lease [Member] |  |
Loss Contingencies [Line Items] |  |
Lease expiration year | 2028 |

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