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Acquisitions - Additional Information (Detail) | 3 Months Ended
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Sep. 30, 2020 Plant
Business Combinations [Abstract] |
Business combination, number of ready mixed concrete operations acquired | 4

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- Definition Business Combination, number of ready mixed concrete operations acquired. + References No definition available. + Details
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration