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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
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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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Number of another entity's patents that the entity was found not to have infringed.

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Number of pending claims pertaining to a loss contingency.

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-Paragraph 4
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Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

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Surety bonds amount outstanding.

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