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Segment Information - Additional Information (Detail) | 6 Months Ended
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Sep. 30, 2017 Location Facility Terminal Plant Segment Center JointVentures
Segment Reporting Information [Line Items] |
Number of operating business segments | Segment | 5
Cement plant locations | Location | 7
Slag grinding facility | Facility | 1
Cement distribution terminals | Terminal | 17
Gypsum wallboard plants | Plant | 5
Readymix concrete batch plant | Plant | 17
Aggregates processing plant | Plant | 4
Number of frac sand processing facilities | Facility | 2
Number of frac sand drying facilities | Facility | 3
Number of frac sand trans-load locations | Location | 6
Number of frac sand distribution centers | Center | 11
Proportionate consolidation of share of Joint Venture's revenues and operating earnings | 50.00%
Cement [Member] |
Segment Reporting Information [Line Items] |
Number of Joint Venture | JointVentures | 1

X
- Definition Aggregates processing plant. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

X
- Definition Cement distribution terminals. + References No definition available. + Details
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X
- Definition Cement plant locations. + References No definition available. + Details
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X
- Definition Gypsum wallboard plants. + References No definition available. + Details
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- Definition Number of frac sand distribution centers. + References No definition available. + Details
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- Definition Number of frac sand drying facilities. + References No definition available. + Details
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- Definition Number of frac sand processing facilities. + References No definition available. + Details
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- Definition Number of frac sand trans-load locations. + References No definition available. + Details
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- Definition Number of joint ventures. + References No definition available. + Details
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Period Type: | instant

X
- Definition Readymix plant. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

X
- Definition Segment reporting information proportionate consolidation of joint ventures revenues and operating earnings. + References No definition available. + Details
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- Definition Slag grinding facility. + References No definition available. + Details
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X
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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Period Type: |