Number of quarries distribution facilities and plants.

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- Definition

Number of states with aggregates business sales by destination.

+ References

No definition available.

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- Definition

Significant accounting policies.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Amount of tax (expense) benefit, before reclassification adjustments, related to (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016 USD ($) State	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) Facility State Segment	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Significant Accounting Policies [Line Items]
Number of quarries distribution facilities and plants \| Facility			400
Number of states with aggregates business sales by destination \| State	26		26
Number of reportable segments \| Segment			3
Other comprehensive loss before reclassifications for pension and postretirement benefit plans, tax benefit	$ 2,346,000	$ 6,793,000	$ 2,405,000	$ 6,904,000
Restatement Adjustment \| Other Noncurrent Assets
Significant Accounting Policies [Line Items]
Debt issuance cost		4,130,000		4,130,000	$ 3,588,000
Restatement Adjustment \| Other Current Assets
Significant Accounting Policies [Line Items]
Debt issuance cost		$ 533,000		$ 533,000	$ 533,000
Product Concentration Risk \| Sales Revenue Segment \| Cement
Significant Accounting Policies [Line Items]
Total net sales, percentage			8.00%		11.00%
Product Concentration Risk \| Sales Revenue Segment \| Magnesia Specialties
Significant Accounting Policies [Line Items]
Total net sales, percentage			7.00%		7.00%
Aggregates Product Line \| Product Concentration Risk \| Product Line Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage			56.00%		55.00%
Aggregates-Related Downstream Product Lines \| Product Concentration Risk \| Product Line Sales
Significant Accounting Policies [Line Items]
Total net sales, percentage			29.00%		27.00%