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v3.20.2

Summary of Significant Accounting Policies (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 USD ($) engine | Jun. 30, 2020 USD ($) engine | Jun. 30, 2019 USD ($) engine
Property, Plant and Equipment [Line Items] |  |  |
Number of assets impaired | engine |  | 2 | 4
Asset write-down |  | $ 9.1 | $ 4.4
Contingencies related to COVID-19 |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Number of assets impaired | engine | 2 |  |
Asset write-down | $ 0.5 |  |
Reduction to revenue, rent concessions | $ 3.1 |  |

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