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Exit Activity Costs and Asset Impairments (Narrative) (Details) $ in Thousands |  | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 USD ($) | Jun. 30, 2020 USD ($) facility | Jun. 30, 2019 USD ($) facility
Restructuring and Related Activities [Abstract] |  |  |
Number of facilities closed | facility |  | 1 | 0
Restructuring Cost and Reserve [Line Items] |  |  |
Gain on sale of business |  | $ 1,881 | $ 0
Apartment Tour Application Business |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Proceeds from sale of business | $ 2,000 |  |
Gain on sale of business | $ 1,900 |  |

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