Financial Information Related to Operations by Segment (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2019 USD ($) kT	Dec. 31, 2018 USD ($) kT	Dec. 31, 2019 USD ($) kT	Dec. 31, 2018 USD ($) kT	Mar. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Revenue	$ 350,249	$ 333,285	$ 1,135,372	$ 1,108,540
Less: Joint Venture Revenue	(28,382)	(25,369)	(85,775)	(78,112)
Operating Earnings	98,214	89,928	299,838	298,917
Corporate General and Administrative Expense	(13,794)	(9,408)	(48,506)	(27,333)
Impairment Losses	(224,267)		(224,267)
Litigation Settlements and Losses				(1,800)
Other Non-Operating Income	825	1,292	1,967	2,291
Earnings (Loss) Before Interest and Income Taxes	(139,022)	81,812	29,032	272,075
Interest Expense, Net	(9,543)	(7,294)	(28,526)	(20,743)
Earnings (Loss) before Income Taxes	(148,565)	74,518	506	251,332
Capital Expenditures	23,856	33,002	86,731	126,446
Depreciation, Depletion, and Amortization	28,611	29,785	84,944	91,961
Identifiable Assets	2,130,225		2,130,225		$ 2,169,163
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	400,406	379,265	1,287,601	1,249,398
Operating Earnings	54,180	47,197	156,827	142,078
Operating Segments [Member] \| Wholly-Owned [Member]
Segment Reporting Information [Line Items]
Operating Earnings	43,480	37,690	124,338	113,147
Operating Segments [Member] \| Joint Venture [Member]
Segment Reporting Information [Line Items]
Operating Earnings	10,700	9,507	32,489	28,931
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(21,775)	(20,611)	(66,454)	(62,746)
Cement [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	$ 183,031	$ 163,732	$ 605,357	$ 543,681
Cement Sales Volume \| kT	1,439	1,344	4,767	4,412
Operating Earnings	$ 54,180	$ 47,197	$ 156,827	$ 142,078
Capital Expenditures	7,379	17,691	26,125	51,524
Depreciation, Depletion, and Amortization	14,189	$ 13,242	42,275	$ 38,909
Identifiable Assets	$ 1,282,081		$ 1,282,081		1,289,468
Cement [Member] \| Operating Segments [Member] \| Wholly-Owned [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume \| kT	1,199	1,126	4,046	3,740
Cement [Member] \| Operating Segments [Member] \| Joint Venture [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume \| kT	240	218	721	672
Cement [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	$ (6,174)	$ (3,518)	$ (17,130)	$ (11,769)
Concrete and Aggregates [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	47,147	30,841	142,895	111,425
Operating Earnings	3,334	1,037	15,023	10,621
Capital Expenditures	3,233	2,263	9,324	4,786
Depreciation, Depletion, and Amortization	3,105	2,049	8,050	6,154
Identifiable Assets	139,769		139,769		95,084
Concrete and Aggregates [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(350)	(346)	(1,134)	(1,178)
Gypsum Wallboard [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	125,070	130,954	380,454	402,978
Operating Earnings	38,484	43,543	114,872	139,694
Capital Expenditures	273	2,054	8,647	8,533
Depreciation, Depletion, and Amortization	5,050	4,978	15,149	15,009
Identifiable Assets	367,833		367,833		372,206
Paperboard [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	37,813	39,638	122,360	126,048
Operating Earnings	9,021	7,475	29,060	26,078
Capital Expenditures	12,885	1,486	42,484	7,896
Depreciation, Depletion, and Amortization	2,244	2,150	6,610	6,387
Identifiable Assets	169,508		169,508		138,614
Paperboard [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(15,251)	(16,747)	(48,190)	(49,799)
Oil and Gas Proppants [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	7,345	14,100	36,535	65,266
Operating Earnings	(6,805)	(9,324)	(15,944)	(19,554)
Capital Expenditures	86	5,818	151	48,684
Depreciation, Depletion, and Amortization	3,445	6,964	11,087	24,403
Identifiable Assets	18,029		18,029		236,357
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Capital Expenditures		3,690		5,023
Depreciation, Depletion, and Amortization	578	$ 402	1,773	$ 1,099
Identifiable Assets	$ 153,005		$ 153,005		$ 37,434

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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