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Commitments and Contingencies - Additional Information (Detail) $ in Millions | Jul. 15, 2021 petition | Jun. 30, 2021 USD ($) | Mar. 15, 2021 patent | Dec. 31, 2020 USD ($) | Sep. 18, 2020 petition patent | Jul. 21, 2020 patent | Sep. 17, 2019 patent | Feb. 28, 2018 claim | Feb. 16, 2018 claim | Feb. 05, 2018 claim | Dec. 31, 2017 claim
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Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Outstanding letters of credit |  | $ 16.9 |  |  |  |  |  |  |  |  |
Outstanding surety bonds |  | 10.6 |  | $ 10.1 |  |  |  |  |  |  |
Number of patents infringed | patent |  |  | 2 |  | 3 | 5 | 7 |  |  |  |
Number of petitions filed | petition |  |  |  |  | 4 |  |  |  |  |  |
Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Loss contingency, patents found not infringed, number | petition | 2 |  |  |  |  |  |  |  |  |  |
Class Action Lawsuits |  |  |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of pending claims | claim |  |  |  |  |  |  |  |  |  |  | 2
Shareholder Derivative Lawsuits |  |  |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of pending claims | claim |  |  |  |  |  |  |  | 4 | 2 | 2 |
Homes under contract to purchase that have not closed |  |  |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |
Value of homes under contract that have not closed |  | $ 1,200.0 |  |  |  |  |  |  |  |  |

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