Acquisition litigation and other expense.

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Earnings before interest and taxes.

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Sales volume in tons.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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Financial Information Related to Operations by Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]
Net Revenues	$ 223,780us-gaap_SalesRevenueGoodsNet	$ 291,529us-gaap_SalesRevenueGoodsNet	$ 284,808us-gaap_SalesRevenueGoodsNet	$ 266,251us-gaap_SalesRevenueGoodsNet	$ 189,894us-gaap_SalesRevenueGoodsNet	$ 228,812us-gaap_SalesRevenueGoodsNet	$ 252,646us-gaap_SalesRevenueGoodsNet	$ 227,044us-gaap_SalesRevenueGoodsNet	$ 1,066,368us-gaap_SalesRevenueGoodsNet	$ 898,396us-gaap_SalesRevenueGoodsNet	$ 642,562us-gaap_SalesRevenueGoodsNet
Operating Earnings									302,301us-gaap_OperatingIncomeLoss	224,638us-gaap_OperatingIncomeLoss	134,520us-gaap_OperatingIncomeLoss
Corporate General and Administrative Expense									(30,751)us-gaap_GeneralAndAdministrativeExpense	(24,552)us-gaap_GeneralAndAdministrativeExpense	(23,918)us-gaap_GeneralAndAdministrativeExpense
Acquisition, Litigation and Other Expense									(6,880)		(10,683)
Earnings Before Interest and Income Taxes									264,670exp_EarningsBeforeInterestAndTaxes	200,086exp_EarningsBeforeInterestAndTaxes	99,919exp_EarningsBeforeInterestAndTaxes
Interest Expense, Net									(11,743)us-gaap_InterestExpense	(18,282)us-gaap_InterestExpense	(15,823)us-gaap_InterestExpense
Earnings before Income Taxes	44,698	77,866	74,577	55,786	29,767	48,833	58,688	44,516	252,927	181,804	84,096
Capital Expenditures									111,573	59,490	53,011
Depreciation, Depletion and Amortization									76,299	70,021	56,850
Identifiable Assets	1,882,591us-gaap_Assets				1,511,529us-gaap_Assets				1,882,591us-gaap_Assets	1,511,529us-gaap_Assets	1,476,233us-gaap_Assets
Joint Venture [Member]
Segment Reporting Information [Line Items]
Net Revenues									(126,220)	(111,393)	(96,322)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									1,258,121	1,071,883	788,871
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net Revenues									65,533	62,094	49,987
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Operating Earnings									3,201	1,368	21
Capital Expenditures									135	249	10
Identifiable Assets	25,655				31,777				25,655	31,777	29,000
Cement [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									488,644	438,224	304,125
Cement Sales Volume									4,799	4,593	3,303
Operating Earnings									117,527	89,486	46,228
Capital Expenditures									27,086	12,226	15,583
Depreciation, Depletion and Amortization									31,839	31,829	20,658
Identifiable Assets	777,956				762,578				777,956	762,578	756,158
Cement [Member] \| Operating Segments [Member] \| Joint Venture [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume									1,055	1,013	913
Operating Earnings									44,967	37,811	32,507
Cement [Member] \| Operating Segments [Member] \| Wholly-Owned [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume									3,744	3,580	2,390
Operating Earnings									72,560	51,675	13,721
Cement [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net Revenues									9,598	8,952	2,850
Gypsum Wallboard [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									437,514	387,016	306,529
Operating Earnings									145,871	114,852	69,712
Capital Expenditures									7,129	4,825	2,682
Depreciation, Depletion and Amortization									20,092	20,981	21,045
Identifiable Assets	403,279				412,566				403,279	412,566	425,866
Paperboard [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									142,690	130,178	121,930
Operating Earnings									31,512	23,610	25,200
Capital Expenditures									1,888	3,354	804
Depreciation, Depletion and Amortization									8,251	8,716	8,824
Identifiable Assets	123,519				125,045				123,519	125,045	129,226
Paperboard [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net Revenues									55,060	52,119	46,393
Oil and Gas Proppants [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									81,381	19,557
Operating Earnings									(2,546)	(4,890)	(1,253)
Capital Expenditures									61,484	34,264
Depreciation, Depletion and Amortization									8,839	1,707
Identifiable Assets	455,572				92,199				455,572	92,199	48,929
Concrete and Aggregates [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Revenues									107,892	96,908	56,287
Operating Earnings									6,736	212	(5,388)
Capital Expenditures									13,851	4,572	33,932
Depreciation, Depletion and Amortization									5,533	5,205	5,212
Identifiable Assets	96,610				87,364				96,610	87,364	87,054
Concrete and Aggregates [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net Revenues									875	1,023	744
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization									$ 1,745	$ 1,583	$ 1,111