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Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Feb. 23, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Gain (loss) on disposal |  |  |  | $ 0 | $ 1,881
Discontinued Operations, Disposed of by Sale | Industrial Business Segment |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Net proceeds | $ 38,000 |  |  |  |
Net proceeds, seller note | 13,000 |  |  |  |
Estimated pre-tax gain (loss) |  |  | $ (30,000) |  |
Gain (loss) on disposal | $ (29,600) |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Apartment Tour Application Business |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Gain (loss) on disposal |  | $ 1,900 |  |  |
Proceeds from sale of business |  | $ 2,000 |  |  |

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