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Acquisitions - Additional Information (Detail) - USD ($) |  |  | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
May 17, 2021 | Apr. 01, 2021 | Sep. 30, 2021 | Dec. 31, 2020
Business Acquisition [Line Items] |  |  |  |
Combined acquired goodwill |  |  | $ 132,387,000 | $ 28,197,000
Goodwill deductible for tax purpose, period |  |  | 15 years |
Combined federal and state tax rate |  |  | 28.00% |
Customer Relationships [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired intangible assets, expected useful life |  |  | 8 years | 11 years
Trade Name |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired intangible assets, expected useful life |  |  | 8 years |
Non-compete [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired intangible assets, expected useful life |  |  | 5 years |
Customer Backlog [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquired intangible assets, expected useful life |  |  | 6 months |
Design Space Modular Buildings PNW, LP [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Purchase of assets | $ 267,300,000 |  |  |
Business acquisition, transaction costs | 1,000,000.0 |  |  |
Combined acquired goodwill | $ 101,874,000 |  |  |
GRS Holding LLC, DBA Kitchens To Go [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Purchase of assets |  | $ 18,300,000 |  |
Business acquisition, transaction costs |  | 300,000 |  |
Combined acquired goodwill |  | $ 2,322,000 |  |
Design Space and Kitchens To Go [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Combined acquired goodwill |  |  | $ 104,196 |

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