Eagle Materials (EXP) 10-Q 30 Oct 18 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Sep. 30, 2018	Oct. 26, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,019
Document Fiscal Period Focus	Q2
Trading Symbol	EXP
Entity Registrant Name	EAGLE MATERIALS INC
Entity Central Index Key	918,646
Current Fiscal Year End Date	--03-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		46,889,378

Consolidated Statements of Earn

Consolidated Statements of Earnings (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Revenue	$ 381,499	$ 376,315	$ 775,255	$ 742,436
Cost of Goods Sold	283,568	279,561	585,690	559,623
Gross Profit	97,931	96,754	189,565	182,813
Equity in Earnings of Unconsolidated Joint Venture	10,173	11,955	19,424	21,831
Corporate General and Administrative Expense	(9,922)	(9,821)	(17,925)	(19,500)
Litigation Settlements and Losses			(1,800)
Other Non-Operating Income	428	887	999	1,644
Interest Expense, Net	(6,817)	(7,456)	(13,449)	(14,939)
Earnings before Income Taxes	91,793	92,319	176,814	171,849
Income Taxes	(19,190)	(28,957)	(37,872)	(53,605)
Net Earnings	$ 72,603	$ 63,362	$ 138,942	$ 118,244
EARNINGS PER SHARE
Basic	$ 1.54	$ 1.32	$ 2.93	$ 2.46
Diluted	$ 1.53	$ 1.31	$ 2.90	$ 2.43
AVERAGE SHARES OUTSTANDING
Basic	47,219,532	48,053,733	47,453,655	48,087,625
Diluted	47,563,818	48,504,767	47,853,472	48,579,984
CASH DIVIDENDS PER SHARE	$ 0.10	$ 0.10	$ 0.20	$ 0.20

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Earnings (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net Earnings	$ 72,603	$ 63,362	$ 138,942	$ 118,244
Net Actuarial Change in Defined Benefit Plans:
Amortization of net actuarial loss	73	314	146	628
Tax expense	(17)	(117)	(34)	(234)
Comprehensive Earnings	$ 72,659	$ 63,559	$ 139,054	$ 118,638

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Current Assets -
Cash and Cash Equivalents	$ 10,002	$ 9,315
Restricted Cash		38,753
Accounts and Notes Receivable, net	174,550	141,685
Inventories	238,869	258,159
Income Tax Receivable	5,924	5,750
Prepaid and Other Assets	7,751	5,073
Total Current Assets	437,096	458,735
Property, Plant, and Equipment -	2,636,249	2,586,528
Less: Accumulated Depreciation	(1,011,511)	(991,229)
Property, Plant, and Equipment, net	1,624,738	1,595,299
Notes Receivable	3,144	115
Investment in Joint Venture	60,482	60,558
Goodwill and Intangible Assets, net	237,738	239,342
Other Assets	16,314	13,954
Total Assets	2,379,512	2,368,003
Current Liabilities -
Accounts Payable	92,479	73,459
Accrued Liabilities	62,223	105,870
Total Current Liabilities	154,702	179,329
Long-term Debt	631,257	620,922
Other Long-term Liabilities	31,099	31,096
Deferred Income Taxes	129,851	118,966
Total Liabilities	946,909	950,313
Stockholders’ Equity –
Preferred Stock, Par Value $0.01; Authorized 5,000,000 Shares; None Issued
Common Stock, Par Value $0.01; Authorized 100,000,000 Shares; Issued and Outstanding 47,189,378 and 48,282,784 Shares, respectively	472	483
Capital in Excess of Par Value	7,752	122,379
Accumulated Other Comprehensive Losses	(3,900)	(4,012)
Retained Earnings	1,428,279	1,298,840
Total Stockholders’ Equity	1,432,603	1,417,690
Liabilities and Stockholders' Equity, Total	$ 2,379,512	$ 2,368,003

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares	Sep. 30, 2018	Mar. 31, 2018
Statement Of Financial Position [Abstract]
Preferred Stock, Par Value	$ 0.01	$ 0.01
Preferred Stock, Authorized	5,000,000	5,000,000
Preferred Stock, Issued	0	0
Common Stock, Par Value	$ 0.01	$ 0.01
Common Stock, Authorized	100,000,000	100,000,000
Common Stock, Issued	47,189,378	48,282,784
Common Stock, Outstanding	47,189,378	48,282,784

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net Earnings	$ 138,942	$ 118,244
Adjustments to Reconcile Net Earnings to Net Cash Provided by Operating Activities, Net of Effect of Non-Cash Activity -
Depreciation, Depletion and Amortization	62,176	59,253
Deferred Income Tax Provision	10,851	1,077
Stock Compensation Expense	7,559	7,235
Equity in Earnings of Unconsolidated Joint Venture	(19,424)	(21,831)
Distributions from Joint Venture	19,500	17,500
Changes in Operating Assets and Liabilities:
Accounts and Notes Receivable	(35,894)	(30,361)
Inventories	19,290	13,856
Accounts Payable and Accrued Liabilities	(24,399)	(14,905)
Other Assets	(3,551)	2,202
Income Taxes Payable (Receivable)	(174)	478
Net Cash Provided by Operating Activities	174,876	152,748
CASH FLOWS FROM INVESTING ACTIVITIES
Additions to Property, Plant, and Equipment	(93,444)	(44,851)
Acquisition Spending		(36,761)
Proceeds from Sale of Property, Plant, and Equipment	2,281
Net Cash Used in Investing Activities	(91,163)	(81,612)
CASH FLOWS FROM FINANCING ACTIVITIES
Increase (Decrease) in Credit Facility	10,000	(30,000)
Dividends Paid to Stockholders	(9,582)	(9,709)
Purchase and Retirement of Common Stock	(122,404)	(24,903)
Proceeds from Stock Option Exercises	1,992	20,426
Shares Redeemed to Settle Employee Taxes on Stock Compensation	(1,785)	(2,455)
Net Cash Used in Financing Activities	(121,779)	(46,641)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	(38,066)	24,495
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	48,068	6,561
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	$ 10,002	$ 31,056

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Losses [Member]
Beginning balance at Mar. 31, 2017	$ 1,203,450	$ 485	$ 149,014	$ 1,061,347	$ (7,396)
Net Earnings	256,632			256,632
Stock Option Exercises and Restricted Share Vesting	24,264	3	24,261
Purchase and Retirement of Common Stock	(61,078)	(5)	(61,073)
Dividends to Stockholders	(19,404)			(19,404)
Stock Compensation Expense	14,079		14,079
Cumulative Impact of the Adoption of ASU 2016-09			713	(713)
Reclassification of Income Tax Effects to Retained Earnings				978	(978)
Shares Redeemed to Settle Employee Taxes	(4,974)		(4,974)
Other	359		359
Unfunded Pension Liability, net of tax	4,362				4,362
Ending Balance at Mar. 31, 2018	1,417,690	483	122,379	1,298,840	(4,012)
Net Earnings	138,942			138,942
Stock Option Exercises and Restricted Share Vesting	1,992		1,992
Purchase and Retirement of Common Stock	(122,404)	(12)	(122,392)
Dividends to Stockholders	(9,503)			(9,503)
Stock Compensation Expense	7,559	1	7,558
Shares Redeemed to Settle Employee Taxes	(1,785)		(1,785)
Unfunded Pension Liability, net of tax	112				112
Ending Balance at Sep. 30, 2018	$ 1,432,603	$ 472	$ 7,752	$ 1,428,279	$ (3,900)

BASIS OF PRESENTATION

BASIS OF PRESENTATION	6 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
BASIS OF PRESENTATION	(A) BASIS OF PRESENTATION The accompanying unaudited consolidated financial statements as of and for the three and six-month periods ended September 30, 2018 include the accounts of Eagle Materials Inc. and its majority-owned subsidiaries (collectively, the Company, us, or we) and have been prepared by the Company, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission. These unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our Annual Report on Form 10-K filed with the Securities and Exchange Commission on May 23, 2018. Certain information and footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted pursuant to such rules and regulations, although we believe that the disclosures are adequate to make the information presented not misleading. In our opinion, all adjustments (consisting solely of normal recurring adjustments) necessary to present fairly the information in the following unaudited consolidated financial statements of the Company have been included. The results of operations for interim periods are not necessarily indicative of the results for the full year. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Recent Accounting Pronouncements RECENTLY ADOPTED In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) ASU 2014-09, “Revenue from Contracts with Customers.” ASU 2014-09 supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires entities to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. We adopted the new standard on April 1, 2018 using the modified retrospective approach. The adoption of this standard did not affect In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” which revises the accounting for periodic pension and postretirement expense. This ASU requires net periodic benefit cost, with the exception of service cost, to be presented retrospectively as nonoperating expense. Service cost will remain a component of Cost of Goods Sold and represent the only cost of pension and postretirement expense eligible for capitalization. We adopted the standard on April 1, 2018 using the retrospective method for presentation of service cost and other components in the income statement. We prospectively adopted the requirement to limit the capitalization of benefit cost to the service cost component. The impact of adopting this standard was not material to our financial statements . In January 2017, the FASB issued ASU 2017-04 “Simplifying the Test for Goodwill Impairment,” which eliminates the second step of the goodwill impairment test. Under the new standard, an entity should recognize an impairment charge for the amount by which the carrying value of the reporting unit exceeds the reporting unit’s fair value. This standard is effective for us in the first quarter of fiscal 2021. We adopted this standard effective April 1, 2018, and it will be effective for annual goodwill impairment tests in the fourth quarter of fiscal 2019. PENDING ADOPTION In February 2016, the FASB issued ASU 2016-02, “Leases,” which supersedes existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by long‒term leases and to disclose additional quantitative and qualitative information about leasing arrangements. The standard will be effective for us in the first quarter of fiscal 2020, and we will adopt the standard using the modified retrospective approach. We are currently assessing the impact of the ASU on our consolidated financial statements and disclosures, as well as our internal lease accounting processes . In January 2018, the FASB issued ASU 2018-01, “Land Easement Practical Expedient for Transition to Topic 842.” This ASU permits the Company to elect not to evaluate under the new lease guidance land easements that existed or expired before the adoption of the ASU 2016-02 and that were not previously accounted for as leases. We will adopt ASU 2018-01 concurrently with the adoption of ASU 2016-02 in the first quarter of fiscal 2020.

CASH FLOW INFORMATION - SUPPLEM

CASH FLOW INFORMATION - SUPPLEMENTAL	6 Months Ended
	Sep. 30, 2018
Supplemental Cash Flow Elements [Abstract]
CASH FLOW INFORMATION - SUPPLEMENTAL	(B) CASH FLOW INFORMATION—SUPPLEMENTAL Cash payments made for interest were $13.9 million and $14.6 million for the six months ended September 30, 2018 and 2017, respectively. Net payments made for federal and state income taxes during the six months ended September 30, 2018 and 2017 were $27.4 million and $52.4 million, respectively. We have excluded approximately $5.2 million of non-cash investing activities from the September 30, 2017 Unaudited Consolidated Statement of Cash Flows. The amounts excluded related to fixed asset additions that were accrued at September 30, 2017, and paid during October 2017.

REVENUE

REVENUE	6 Months Ended
	Sep. 30, 2018
Revenue From Contract With Customer [Abstract]
REVENUE	(C) REVENUE On April 1, 2018, we adopted the new accounting standard ASU 2014-09 (Topic 606), “Revenue from Contracts with Customers” and all the related amendments to contracts using the modified retrospective method. The adoption of ASU 2014-09 had no impact on our financial statements at the time of the adoption. We earn Revenue primarily from the sale of products, which include cement, concrete, aggregates, gypsum wallboard, recycled paperboard, and frac sand. The vast majority of Revenue from the sale of cement, concrete, aggregates, and gypsum wallboard are originated by purchase orders from our customers, who are primarily third-party contractors and suppliers. Revenue from our Recycled Paperboard and Oil and Gas Proppants segments is generated primarily through long-term supply agreements that mature between 2018 and 2025. We also earn Revenue from transload services and storage; we recognize Revenue from these services when the product is transferred from the rail car to the truck or silo, or from the silo to the railcar or truck. We invoice customers upon shipment, and our collection terms range from 30-65 days. Revenue from the sale of cement, concrete, aggregates, and gypsum wallboard that is not related to long-term supply agreements is recognized upon shipment of the related products to customers, which is when title and ownership are transferred and the customer is obligated to pay. Revenue from sales under our long-term supply agreements is also recognized upon transfer of control to the customer, which generally occurs at the time the product is shipped from the production facility or transload location. Our long-term supply agreements with customers define, among other commitments, the volume of product that we must provide and the volume that the customer must purchase by the end of the defined periods. Pricing structures under our agreements are generally market‒based but are subject to certain contractual adjustments. Historically the pricing and volume requirements under certain of these contracts have been renegotiated during volatile market conditions. Shortfall amounts, if applicable under these arrangements, are constrained and not recognized as Revenue until agreement is reached with the customer and not subject to the risk of reversal. The Company offers certain of its customers, including those with long‒term supply agreements, rebates and incentives, which we treat as variable consideration. We adjust the amount of revenue recognized for the variable consideration using the most likely amount method based on past history and projected volumes in the rebate and incentive period. Any amounts billed to customers for taxes are excluded from Revenue. The Company has elected to treat freight and delivery charges we pay for the delivery of goods to our customers as a fulfilment activity rather than a separate performance obligation. When we arrange for a third party to deliver products to customers, fees for shipping and handling that are billed to the customer are recorded as Revenue, while costs we incur for shipping and handling are recorded as expenses and included in Cost of Goods Sold. Other Non-Operating Income includes lease and rental income, asset sale income, non-inventoried aggregates sales income, distribution center income, and trucking income, as well as other miscellaneous revenue items and costs that have not been allocated to a business segment. See Footnote (M) to the Unaudited Consolidated Financial Statements for disaggregation of Revenue by segment.

ACCOUNTS AND NOTES RECEIVABLE

ACCOUNTS AND NOTES RECEIVABLE	6 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
ACCOUNTS AND NOTES RECEIVABLE	(D) ACCOUNTS AND NOTES RECEIVABLE Accounts and Notes Receivable have been shown net of the allowance for doubtful accounts of $9.1 million and $8.6 million at September 30, 2018 and March 31, 2018, respectively. We perform ongoing credit evaluations of our customers’ financial condition and generally require no collateral from our customers. The allowance for non-collection of receivables is based upon analysis of economic trends in the construction industry, detailed analysis of the expected collectability of accounts receivable that are past due and the expected collectability of overall receivables. We have no significant credit risk concentration among our diversified customer base. We had Notes Receivable totaling approximately $3.8 million at September 30, 2018, of which approximately $0.7 million has been classified as current and presented with Accounts Receivable on the balance sheet. We lend funds to certain companies in the ordinary course of business, and the notes bear interest, on average, at 4.5%. Remaining unpaid amounts, plus accrued interest, mature in fiscal 2025. The notes are collateralized by certain assets of the borrowers, namely property and equipment, and are generally payable monthly. We monitor the credit risk of each borrower by assessing the timeliness of payments, credit history, credit metrics, and our ongoing interactions with each borrower.

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	6 Months Ended
	Sep. 30, 2018
Equity [Abstract]
STOCKHOLDERS' EQUITY	(E) STOCKHOLDERS’ EQUITY During the six months ended September 30, 2018, we repurchased 1,239,100 shares at an average price of $98.77. Subsequent to September 30, 2018, we repurchased an additional 300,000 shares through October 26, 2018, at an average price of $80.15. Including the repurchases subsequent to September 30, 2018, we have authorization to purchase an additional 2,650,328 shares.

INVENTORIES

INVENTORIES	6 Months Ended
	Sep. 30, 2018
Inventory Disclosure [Abstract]
INVENTORIES	(F) INVENTORIES Inventories are stated at the lower of average cost (including applicable material, labor, depreciation, and plant overhead) or net realizable value, and consist of the following: September 30, March 31, 2018 2018 (dollars in thousands) Raw Materials and Materials-in-Progress $ 105,943 $ 121,628 Finished Cement 24,003 24,089 Aggregates 7,309 7,787 Gypsum Wallboard 7,612 8,477 Paperboard 9,793 8,602 Frac Sand 2,729 1,696 Repair Parts and Supplies 76,048 79,878 Fuel and Coal 5,432 6,002 $ 238,869 $ 258,159

ACCRUED EXPENSES

ACCRUED EXPENSES	6 Months Ended
	Sep. 30, 2018
Payables And Accruals [Abstract]
ACCRUED EXPENSES	(G) ACCRUED EXPENSES Accrued Expenses consist of the following: September 30, March 31 2018 2018 (dollars in thousands) Payroll and Incentive Compensation $ 21,199 $ 25,290 Benefits 13,076 13,785 Interest 3,852 3,852 Property Taxes 8,292 5,422 Power and Fuel 1,473 1,545 Litigation Settlements 345 45,098 Rail Freight 2,012 — Legal 2,185 1,435 Sales and Use Tax 929 890 Other 8,860 8,553 $ 62,223 $ 105,870

SHARE-BASED EMPLOYEE COMPENSATI

SHARE-BASED EMPLOYEE COMPENSATION	6 Months Ended
	Sep. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
SHARE-BASED EMPLOYEE COMPENSATION	(H) S hare On August 7, 2013, our stockholders approved the Eagle Materials Inc. Amended and Restated Incentive Plan (the Plan), which increased the shares we are authorized to issue as awards by 3,000,000 (1,500,000 of which may be stock awards). Under the terms of the Plan, we can issue equity awards, including stock options, restricted stock units (RSUs), restricted stock, and stock appreciation rights to employees of the Company and members of the Board of Directors. Awards that were already outstanding prior to the approval of the Plan on August 7, 2013 remain outstanding. The Compensation Committee of our Board of Directors specifies the terms for grants of equity awards under the Plan. Long-Term Compensation Plans OPTIONS In May 2018, the Compensation Committee of the Board of Directors approved the granting to certain officers and key employees an aggregate of 62,179 performance vesting stock options that will be earned only if certain performance conditions are satisfied (the Fiscal 2019 Employee Performance Stock Option Grant). The performance criteria for the Fiscal 2019 Employee Performance Stock Option Grant is based upon the achievement of certain levels of return on equity (as defined in the option agreements), ranging from 10.0% to 20.0%, for the fiscal year ending March 31, 2019. All stock options will be earned if the return on equity is 20.0% or greater, and the percentage of shares earned will be reduced proportionately to approximately 66.7% if the return on equity is 10.0%. If the Company does not achieve a return on equity of at least 10.0%, all stock options granted will be forfeited. Following any such reduction, restrictions on the earned stock options will lapse ratably over four years, with the initial fourth lapsing promptly following the determination date, and the remaining restrictions lapsing on March 31, 2020 through 2022. The stock options have a term of ten years from the date of grant. The Compensation Committee also approved the granting to the same officers and key employees of 51,814 time vesting stock options, which vest ratably over four years (the Fiscal 2019 Employee Time Vesting Stock Option Grant). In August 2018, we granted 1,741 options to members of the Board of Directors (the Fiscal 2019 Board of Directors Stock Option Grant). Options granted under the Fiscal 2019 Board of Directors Stock Option Grant vest immediately and can be exercised from the date of the grant until their expiration of the tenth anniversary of the date of grant. The Fiscal 2019 Employee Performance Stock Option Grant, the Fiscal 2019 Employee Time Vesting Stock Option Grant, and the Fiscal 2019 Board of Directors Stock Option Grant were valued at the grant date using the Black‒Scholes option pricing model. The weighted average assumptions used in the Black-Scholes models to value the option awards in fiscal 2019 are as follows: 2018 Dividend Yield 1.3 % Expected Volatility 32.7 % Risk Free Interest Rate 2.9 % Expected Life 6.0 years Stock option expense for all outstanding stock option awards totaled approximately $1.0 million and $2.1 million for the three and six months ended September 30, 2018, respectively, and approximately $1.3 million and $2.2 million for the three and six months ended September 30, 2017, respectively. At September 30, 2018, there was approximately $8.5 million of unrecognized compensation cost related to outstanding stock options, which is expected to be recognized over a weighted average period of 2.7 years. The following table represents stock option activity for the six months ended September 30, 2018: Number of Shares Weighted Average Exercise Price Outstanding Options at Beginning of Year 958,136 $ 72.52 Granted 115,734 $ 106.14 Exercised (35,454 ) $ 110.89 Cancelled (2,197 ) $ 100.88 Outstanding Options at End of Year 1,036,219 $ 76.77 Options Exercisable at End of Year 698,207 $ 69.16 Weighted Average Fair Value of Options Granted during the Year $ 33.99 The following table summarizes information about stock options outstanding at September 30, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number of Shares Outstanding Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Outstanding Weighted Average Exercise Price $23.17 - $29.84 65,912 2.85 $ 23.27 65,912 $ 23.27 $33.43 - $37.34 84,582 3.71 $ 33.98 84,582 $ 33.98 $53.22 - $77.67 293,163 6.57 $ 71.27 188,311 $ 70.56 $79.73 - $106.24 592,562 7.50 $ 91.55 359,402 $ 85.12 1,036,219 6.63 $ 76.77 698,207 $ 69.16 At September 30, 2018, the aggregate intrinsic value for outstanding and exercisable options was approximately $8.8 million and $11.2 million, respectively. The total intrinsic value of options exercised during the six months ended September 30, 2018 was approximately $1.9 million. RESTRICTED STOCK In May 2018, the Compensation Committee approved the granting to certain officers and key employees an aggregate of 57,756 shares of performance vesting restricted stock that will be earned if certain performance conditions are satisfied (the Fiscal 2019 Employee Restricted Stock Performance Award). The performance criteria for the Fiscal 2019 Employee Restricted Stock Performance Award is based upon the achievement of certain levels of return on equity (as defined in the award agreement), ranging from 10.0% to 20.0%, for the fiscal year ending March 31, 2019. All restricted shares will be earned if the return on equity is 20.0% or greater, and the percentage of shares earned will be reduced proportionately to approximately 66.7% if the return on equity is 10.0%. If the Company does not achieve a return on equity of at least 10.0%, all awards will be forfeited. Following any such reduction, restrictions on the earned shares will lapse ratably over four years, with the initial fourth lapsing promptly following the determination date, and the remaining restrictions lapsing on March 31, 2020 through 2022. The Compensation Committee also approved the granting to the same officers and key employees of 48,130 shares of time vesting restricted stock, which vest ratably over four years (the Fiscal 2019 Employee Restricted Stock Time Vesting Award). The Fiscal 2019 Employee Restricted Stock Performance Award and the Fiscal 2019 Employee Restricted Stock Time Vesting Award were valued at the closing price of the stock on the date of grant and are being expensed over a four‒year period. In August 2018, we granted 15,950 shares of restricted stock to members of the Board of Directors (the Board of Directors Fiscal 2019 Restricted Stock Award), which vest six months after the grant date. The Board of Directors Fiscal 2019 Restricted Stock Award was valued at the closing price of the stock at the date of the grant and are being expensed over a six-month period. The fair value of restricted stock is based on the stock price at the date of grant. The following table summarizes the activity for nonvested restricted shares during the six months ended September 30, 2018: Number of Shares Weighted Average Grant Date Fair Value Restricted Stock Beginning of Year 328,059 $ 65.76 Granted 121,836 $ 105.13 Vested (46,686 ) $ 61.50 Forfeited (1,990 ) $ 100.88 Nonvested Restricted Stock at End of Year 401,219 $ 78.29 During the six months ended September 30, 2018, the weighted average grant date fair value of restricted shares granted was $105.13. Expense related to restricted shares was approximately $3.1 million and $5.5 million for the three and six months ended September 30, 2018, respectively, and approximately $2.5 million and $5.0 million for the three and six months ended September 30, 2017, respectively. At September 30, 2018, there was approximately $24.5 million of unearned compensation from restricted stock, which will be recognized over a weighted average period of 2.4 years. The number of shares available for future grants of stock options, restricted stock units, stock appreciation rights, and restricted stock under the Plan was 3,984,117 at September 30, 2018.

COMPUTATION OF EARNINGS PER SHA

COMPUTATION OF EARNINGS PER SHARE	6 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
COMPUTATION OF EARNINGS PER SHARE	(I) COMPUTATION OF EARNINGS PER SHARE The calculation of basic and diluted common shares outstanding is as follows: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 Weighted Average Shares of Common Stock Outstanding 47,219,532 48,053,733 47,453,655 48,087,625 Effect of Dilutive Shares: Assumed Exercise of Outstanding Dilutive Options 785,848 1,060,209 807,861 1,159,975 Less Shares Repurchased from Proceeds of Assumed Exercised Options (588,900 ) (801,684 ) (580,350 ) (865,203 ) Restricted Stock Units 147,338 192,509 172,306 197,587 Weighted Average Common Stock and Dilutive Securities Outstanding 47,563,818 48,504,767 47,853,472 48,579,984 Shares Excluded Due to Anti-dilution Effects 181,412 88,729 163,450 76,044

PENSION AND EMPLOYEE BENEFIT PL

PENSION AND EMPLOYEE BENEFIT PLANS	6 Months Ended
	Sep. 30, 2018
Compensation And Retirement Disclosure [Abstract]
PENSION AND EMPLOYEE BENEFIT PLANS	(J) PENSION AND EMPLOYEE BENEFIT PLANS We sponsor several defined benefit pension plans and defined contribution plans which together cover substantially all our employees. Benefits paid under the defined benefit plans covering certain hourly employees are based on years of service and the employee’s qualifying compensation over the last few years of employment. The following table shows the components of net periodic cost for our plans: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Service Cost - Benefits Earned During the Period $ 100 $ 153 $ 200 $ 404 Interest Cost of Projected Benefit Obligation 337 357 674 753 Expected Return on Plan Assets (463 ) (578 ) (926 ) (980 ) Recognized Net Actuarial Loss 58 46 116 473 Amortization of Prior-Service Cost 15 60 30 150 Net Periodic Pension Cost $ 47 $ 38 $ 94 $ 800

INCOME TAXES

INCOME TAXES	6 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
INCOME TAXES	(K) INCOME TAXES The Tax Cuts and Jobs Act (the Act) was enacted on December 22, 2017. The Act, among other changes, reduces the U.S. federal corporate tax rate from 35% to 21%, allows for the immediate 100% deductibility of certain capital expenditures, repeals the domestic production deduction, and further limits the deductibility of certain executive compensation. In December 2017, we recorded a tax benefit after the initial assessment of the tax effects of the Act, and we will continue refining this amount throughout December 2018. We are still analyzing certain aspects of the Act and refining our calculations, which could potentially affect the measurement of our deferred tax balance or give rise to new deferred tax amounts through December 2018. The impact of the Act may differ from our estimate due to changes in the regulations, rulings, guidance, and interpretations issued by the Internal Revenue Service (IRS) and the FASB, as well as interpretations and assumptions made by the Company. The calculation of our estimated annual effective tax rate includes the estimated impact of provisions of the Act, including limitations on the deductibility of certain executive compensation. Such estimates could change as additional information becomes available on these provisions of the Tax Act. Income taxes for the interim period presented have been included in the accompanying financial statements on the basis of an estimated annual effective tax rate. In addition to the amount of tax resulting from applying the estimated annual effective tax rate to pre-tax income, we will, when appropriate, include certain items treated as discrete events to arrive at an estimated overall tax amount. The tax rate for the six months ended September 30, 2018 was approximately 21%, which was lower than the tax rate of 31% for the six months ended September 30, 2017. The decline in the rate was primarily due to the passage of the Act and the corresponding changes in U.S. tax law mentioned above.

LONG-TERM DEBT

LONG-TERM DEBT	6 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
LONG-TERM DEBT	(L) LONG-TERM DEBT Long-term debt consists of the following: September 30, March 31, 2018 2018 (dollars in thousands) Bank Credit Facility $ 250,000 $ 240,000 4.500% Senior Unsecured Notes Due 2026 350,000 350,000 Private Placement Senior Unsecured Notes 36,500 36,500 Total Debt 636,500 626,500 Less: Debt Origination Costs (5,243 ) (5,578 ) Long-term Debt $ 631,257 $ 620,922 Credit Facility We have a $500.0 million revolving credit facility (the Credit Facility), including a swingline loan sublimit of $25.0 million, which terminates on August 2, 2021. Borrowings under the Credit Facility are guaranteed by substantially all of the Company’s subsidiaries. The debt under the Credit Facility is not rated by ratings agencies. At our option, outstanding principal amounts on the Credit Facility bear interest at a variable rate equal to (i) the London Interbank Offered Rate (LIBOR) plus an agreed margin (ranging from 100 to 225 basis points), which is to be established quarterly based upon the Company’s ratio of consolidated EBITDA, defined as earnings before interest, taxes, depreciation, and amortization, to the Company’s consolidated indebtedness (the Leverage Ratio); or (ii) an alternative base rate which is the higher of (a) the prime rate or (b) the federal funds rate plus 1 2 The Credit Facility has a $40.0 million letter of credit facility. Under the letter of credit facility, the Company pays a fee at a per annum rate equal to the applicable margin for Eurodollar loans in effect from time to time plus a one-time letter of credit fee in an amount equal to 0.125% of the initial stated amount. At September 30, 2018, we had $7.8 million of outstanding letters of credit. 4.500% Senior Unsecured Notes Due 2026 On August 2, 2016, the Company issued $350.0 million aggregate principal amount of 4.500% senior notes (Senior Unsecured Notes) due August 2026. Interest on the Senior Unsecured Notes is payable semiannually on February 1 and August 1 of each year until all of the outstanding notes are paid. The Senior Unsecured Notes rank equal to existing and future senior indebtedness, including the Credit Facility and the Private Placement Senior Unsecured Notes. Prior to August 1, 2019, we may redeem with the proceeds of certain equity offerings up to 40% of the original aggregate principal amount of the Senior Unsecured Notes at a redemption price of 104.5% of the principal amount of the notes. On or after August 1, 2019 and prior to August 1, 2021, we may redeem some or all of the Senior Unsecured Notes at a price equal to 100% of the principal amount, plus a “make-whole” premium. Beginning on August 1, 2021, we may redeem some or all of the Senior Unsecured Notes at the redemption prices set forth below (expressed as a percentage of the principal amount being redeemed): Percentage 2021 102.25 % 2022 101.50 % 2023 100.75 % 2024 and thereafter 100.00 % The Senior Unsecured Notes contain covenants that limit our ability and/or our guarantor subsidiaries' ability to create or permit to exist certain liens; enter into sale and leaseback transactions; and consolidate, merge, or transfer all or substantially all of our assets. The Company’s Senior Unsecured Notes are fully, unconditionally, jointly, and severally guaranteed by each of our subsidiaries that are guarantors under the Credit Facility and Private Placement Senior Unsecured Notes. See Footnote (Q) to the Unaudited Consolidated Financial Statements for more information on the guarantors of the Senior Public Notes. Private Placement Senior Unsecured Notes On October 2, 2007, in a private placement transaction, we entered into a Note Purchase Agreement (the 2007 Note Purchase Agreement) in connection with our sale of $200.0 million of senior unsecured notes, designated as Series 2007A Senior Notes (the Series 2007A Senior Unsecured Notes). The Series 2007A Senior Unsecured Notes, which are guaranteed by substantially all of our subsidiaries, were sold at par and issued in four tranches. At September 30, 2018, the amount outstanding for the remaining tranche is as follows: Principal Maturity Date Interest Rate Tranche D $36.5 million October 2, 2019 6.48 % Interest for the Series 2007A Senior Unsecured Notes is payable semi-annually April 2 and October 2 of each year until all principal is paid for the respective tranche. Our obligations under the 2007 Note Purchase Agreement are equal in right of payment with all other senior, unsecured indebtedness of the Company, including our indebtedness under the Credit Facility and Senior Unsecured Notes. The 2007 Note Purchase Agreement contains customary restrictive covenants, including, but not limited to, covenants that place limits on our ability to encumber our assets, to incur additional debt, to sell assets, or to merge or consolidate with third parties. The 2007 Note Purchase Agreement requires us to maintain a Consolidated Debt to Consolidated EBITDA (calculated as consolidated indebtedness to consolidated earnings before interest, taxes, depreciation, depletion, amortization, certain transaction-related deductions, and other non-cash charges) ratio of 3.50 to 1.00 or less, and to maintain an interest coverage ratio (Consolidated EBITDA to Consolidated Interest Expense [calculated as consolidated EBITDA, as defined above, to consolidated interest expense]) of at least 2.50:1.00. In addition, the 2007 Note Purchase Agreement requires the Company to ensure that at all times either (i) Consolidated Total Assets equal at least 80% of the consolidated total assets of the Company and its subsidiaries, determined in accordance with GAAP; or (ii) consolidated Total Revenue of the Company and its restricted subsidiaries for the period of four consecutive fiscal quarters most recently ended equals at least 80% of the consolidated Total Revenue of the Company and its Subsidiaries during such period. We are in compliance with all financial ratios and tests at September 30, 2018. Pursuant to a Subsidiary Guaranty Agreement, substantially all of our subsidiaries have guaranteed the punctual payment of all principal, interest, and make-whole amounts (as defined in the 2007 Note Purchase Agreement) on the Series 2007A Senior Unsecured Notes and the other payment and performance obligations of the Company contained in the 2007 Note Purchase Agreement. We are permitted, at our option and without penalty, to prepay from time to time at least 10% of the original aggregate principal amount of the Series 2007A Senior Unsecured Notes at 100% of the principal amount to be prepaid, together with interest accrued on such amount to be prepaid to the date of payment, plus a make-whole amount. The make-whole amount is computed by discounting the remaining scheduled principal and interest payments at a discount rate of 50 basis points above the yield to maturity of U.S. Treasury securities having a maturity equal to the remaining average life of the Series 2007A Senior Unsecured Notes being prepaid. Other Information We lease one of our cement plants from the city of Sugar Creek, Missouri. The city of Sugar Creek issued industrial revenue bonds to partly finance improvements to the cement plant. The lease payments due to the city of Sugar Creek under the cement plant lease, which was entered into upon the sale of the industrial revenue bonds, are equal in amount to the payments required to be made by the city of Sugar Creek to the holders of the industrial revenue bonds. Because we hold all outstanding industrial revenue bonds, no debt is reflected on our financial statements in connection with our lease of the cement plant. Upon expiration of the lease in fiscal 2021, we have the option to purchase the cement plant for a nominal amount.

SEGMENT INFORMATION

SEGMENT INFORMATION	6 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
SEGMENT INFORMATION	(M) SEGMENT INFORMATION Operating segments are defined as components of an enterprise that engage in business activities that earn revenue, incur expenses, and prepare separate financial information that is evaluated regularly by our chief operating decision maker in order to allocate resources and assess performance. We are a leading supplier of heavy construction materials, light building materials, and materials used for oil and natural gas extraction in the United States. Our products are commodities that are essential in commercial and residential construction; public construction projects; projects to build, expand, and repair roads and highways; and in oil and natural gas extraction. Our business is organized into three sectors within which there are five reportable business segments. The Heavy Materials sector includes the Cement and Concrete and Aggregates segments. The Light Materials sector includes the Gypsum Wallboard and Recycled Paperboard segments. The Oil and Gas Proppants segment produces frac sand used in oil and gas exploration and extraction. Our operations are conducted in the U.S. and include the mining of limestone for the manufacture, production, distribution, and sale of portland cement (a basic construction material that is the essential binding ingredient in concrete); the grinding and sale of slag; the mining of gypsum for the manufacture and sale of gypsum wallboard; the manufacture and sale of recycled paperboard to the gypsum wallboard industry and other paperboard converters; the sale of readymix concrete; and the mining and sale of aggregates (crushed stone, sand, and gravel) and sand used in hydraulic fracturing (frac sand). We operate seven cement plants, one slag grinding facility, 18 cement distribution terminals, five gypsum wallboard plants, a gypsum wallboard distribution center, a recycled paperboard mill, 17 readymix concrete batch plants, four aggregates processing plants, two frac sand processing facilities, three frac sand drying facilities, and six frac sand trans-load locations. The principal markets for our cement products are Texas, Illinois, the central plains, Michigan, Iowa, the Rocky Mountains, northern Nevada, southern Ohio, and northern California. We distribute gypsum wallboard and recycled paperboard throughout the continental U.S., with the exception of the Northeast. Concrete and aggregates are sold to local readymix producers and paving contractors in the Austin, Texas area, the region north of Sacramento, California; and the greater Kansas City, Missouri area. Frac sand is currently sold into shale deposits across the United States. Other segment operations that are not material to our business are included in Other. We conduct one of our seven cement plant operations, Texas Lehigh Cement Company LP, in Buda, Texas, through a Joint Venture. For segment reporting purposes only, we proportionately consolidate our 50% share of the Joint Venture’s Revenue and Operating Earnings, consistent with the way management reports the segments within the Company for making operating decisions and assessing performance. We account for intersegment sales at market prices. The following table sets forth certain financial information relating to our operations by segment: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Revenue - Cement $ 193,161 $ 191,650 $ 379,949 $ 374,585 Concrete and Aggregates 39,744 43,431 80,584 87,350 Gypsum Wallboard 129,609 123,068 272,024 249,881 Paperboard 41,277 45,359 86,410 89,772 Oil and Gas Proppants 19,080 22,022 40,838 40,932 Other 4,386 — 10,328 — 427,257 425,530 870,133 842,520 Less: Intersegment Revenue (20,279 ) (23,215 ) (42,135 ) (45,914 ) Less: Joint Venture Revenue (25,479 ) (26,000 ) (52,743 ) (54,170 ) $ 381,499 $ 376,315 $ 775,255 $ 742,436 For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Intersegment Revenue - Cement $ 4,073 $ 4,654 $ 8,251 $ 9,583 Concrete and Aggregates 501 402 832 815 Paperboard 15,705 18,159 33,052 35,516 $ 20,279 $ 23,215 $ 42,135 $ 45,914 Cement Sales Volume (M tons) - Wholly Owned 1,339 1,343 2,614 2,611 Joint Venture 218 227 454 470 1,557 1,570 3,068 3,081 For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Operating Earnings - Cement $ 57,547 $ 58,752 $ 94,881 $ 101,933 Concrete and Aggregates 4,100 5,619 9,584 11,640 Gypsum Wallboard 45,671 39,575 96,151 83,396 Paperboard 8,609 6,517 18,603 11,455 Oil and Gas Proppants (7,921 ) (1,754 ) (10,612 ) (3,780 ) Other 98 — 382 — Sub-Total 108,104 108,709 208,989 204,644 Corporate General and Administrative Expense (9,922 ) (9,821 ) (17,925 ) (19,500 ) Litigation Settlements and Losses — — (1,800 ) — Other Non-Operating Income 428 887 999 1,644 Earnings Before Interest and Income Taxes 98,610 99,775 190,263 186,788 Interest Expense, net (6,817 ) (7,456 ) (13,449 ) (14,939 ) Earnings Before Income Taxes $ 91,793 $ 92,319 $ 176,814 $ 171,849 Cement Operating Earnings - Wholly Owned $ 47,374 $ 46,797 $ 75,457 $ 80,102 Joint Ventures 10,173 11,955 19,424 21,831 $ 57,547 $ 58,752 $ 94,881 $ 101,933 Capital Expenditures - Cement $ 14,220 $ 13,014 $ 33,833 $ 20,732 Concrete and Aggregates 459 1,118 2,523 2,530 Gypsum Wallboard 4,124 5,219 6,479 10,861 Paperboard 5,345 659 6,410 1,423 Oil and Gas Proppants 14,827 13,781 42,463 14,360 Other, net 1,396 140 1,736 185 $ 40,371 $ 33,931 $ 93,444 $ 50,091 Depreciation, Depletion and Amortization - Cement $ 12,746 $ 12,662 $ 25,667 $ 25,141 Concrete and Aggregates 2,052 1,929 4,105 3,844 Gypsum Wallboard 5,201 4,473 10,031 8,915 Paperboard 2,128 2,172 4,237 4,309 Oil and Gas Proppants 9,398 8,518 16,537 16,124 Corporate and Other 801 552 1,599 920 $ 32,326 $ 30,306 $ 62,176 $ 59,253 September 30, March 31, 2018 2018 (dollars in thousands) Identifiable Assets Cement $ 1,274,535 $ 1,247,504 Concrete and Aggregates 104,166 104,851 Gypsum Wallboard 378,902 386,041 Paperboard 127,026 123,819 Oil and Gas Proppants 428,356 401,421 Other, net 66,527 104,367 $ 2,379,512 $ 2,368,003 Segment operating earnings, including the proportionately consolidated 50% interest in the revenue and expenses of the Joint Venture, represent Revenue, less direct operating expenses, segment Depreciation, and segment Selling, General and Administrative expenses. We account for intersegment sales at market prices. Corporate assets consist primarily of cash and cash equivalents, general office assets, miscellaneous other assets. The basis used to disclose Identifiable Assets; Capital Expenditures; and Depreciation, Depletion, and Amortization conforms with the equity method, and is similar to how we disclose these accounts in our Unaudited Consolidated Balance Sheets and Unaudited Consolidated Statements of Earnings The segment breakdown of Goodwill is as follows: September 30, March 31, 2018 2018 (dollars in thousands) Cement $ 74,214 $ 74,214 Gypsum Wallboard 116,618 116,618 Paperboard 7,538 7,538 Corporate and Other 6,841 6,841 $ 205,211 $ 205,211 Summarized financial information for the Joint Venture that is not consolidated is set out below (this summarized financial information includes the total amount for the Joint Venture and not our 50% interest in those amounts): For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Revenue $ 51,859 $ 54,000 $ 107,510 $ 111,818 Gross Margin $ 21,877 $ 24,938 $ 42,018 $ 46,251 Earnings Before Income Taxes $ 20,345 $ 23,910 $ 38,849 $ 43,662 September 30, March 31, 2018 2018 (dollars in thousands) Current Assets $ 67,861 $ 71,089 Non-Current Assets $ 67,679 $ 66,856 Current Liabilities $ 18,191 $ 20,671

INTEREST EXPENSE

INTEREST EXPENSE	6 Months Ended
	Sep. 30, 2018
Banking And Thrift Interest [Abstract]
INTEREST EXPENSE	(N) INTEREST EXPENSE The following components are included in Interest Expense, net: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Interest Income $ (110 ) $ (3 ) $ (112 ) $ (6 ) Interest Expense 6,660 7,153 13,002 14,329 Other Expenses 267 306 559 616 Interest Expense, net $ 6,817 $ 7,456 $ 13,449 $ 14,939 Interest Income includes interest on investments of excess cash. Components of Interest Expense include interest associated with the Credit Facility, Senior Unsecured Notes, Private Placement Senior Unsecured Notes, and commitment fees based on the unused portion of the Credit Facility. Other Expenses include amortization of debt issuance costs and credit facility costs.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Sep. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	(O) COMMITMENTS AND CONTINGENCIES We have certain deductible limits under our workers’ compensation and liability insurance policies for which reserves are established based on the undiscounted estimated costs of known and anticipated claims. We have entered into standby letter of credit agreements relating to workers’ compensation and auto and general liability self-insurance. At September 30, 2018, we had contingent liabilities under these outstanding letters of credit of approximately $7.8 million. In the ordinary course of business, we execute contracts involving indemnifications that are standard in the industry and indemnifications specific to a transaction such as the sale of a business. These indemnifications may include claims relating to any of the following: environmental and tax matters; intellectual property rights; governmental regulations and employment-related matters; customer, supplier, and other commercial contractual relationships; construction contracts and financial matters. While the maximum amount to which the Company may be exposed under such agreements cannot be estimated, management believes these indemnifications will not have a material adverse effect on our consolidated financial position, results of operations, or cash flows. We currently have no outstanding guarantees. We are currently contingently liable for performance under $27.7 million in performance bonds required by certain states and municipalities and their related agencies. The bonds are principally for certain reclamation obligations and mining permits. We have indemnified the underwriting insurance company against any exposure under the performance bonds. In our past experience, no material claims have been made against these financial instruments. Domestic Wallboard Antitrust Litigation Since late December 2012, several purported class action lawsuits were filed in various United States District Courts, including the Eastern District of Pennsylvania, Western District of North Carolina, and the Northern District of Illinois, against the Company and the Company’s subsidiary, American Gypsum Company LLC (American Gypsum), alleging that the defendant wallboard manufacturers conspired to fix the price of drywall sold in the United States in violation of federal antitrust laws, and in some cases related provisions of state law. In addition to American Gypsum, the defendants in these lawsuits included certain other wallboard manufacturers. These cases were subsequently transferred and consolidated to the Eastern District of Pennsylvania for coordinated pretrial proceedings. The plaintiffs in the consolidated class action complaints asserted claims on behalf of purported classes of direct purchasers or end users of wallboard from January 1, 2012 to the present for unspecified monetary damages (including treble damages) and in some cases injunctive relief. The Company and American Gypsum denied all allegations that they conspired to increase the price of drywall and asserted affirmative defenses to the plaintiffs’ claims. Following completion of the initial discovery, the Company and remaining co-defendants moved for summary judgment. On February 18, 2016, the court denied the Company’s motion for summary judgment. On August 23, 2017, the court granted the direct purchaser plaintiffs’ motion for class certification and certified a class consisting of all persons or entities that purchased paper-backed gypsum wallboard in the United States from January 1, 2012 through January 31, 2013 directly from American Gypsum, the Company, Lafarge, New NGC, PABCO, USG, and/or L&W Supply Corporation (which was a subsidiary of USG Corporation during the class period). In addition, on August 24, 2017, the court denied the indirect purchaser’s motion for class certification. On December 29, 2017, American Gypsum and the Company, as well as New NGC and PABCO, which are not affiliated with the Company, entered into a settlement agreement (the Direct Purchaser Settlement Agreement) with counsel representing the direct purchaser class to settle all claims made against the Company, American Gypsum, New NGC, and PABCO in the direct purchaser class action. The Direct Purchaser Settlement Agreement, in which the Company and American Gypsum deny all wrongdoing, also includes releases by the participating class members of the Company and American Gypsum as well as their subsidiaries, affiliates, and other related parties, for the time period from January 1, 2012, through the date of execution of the Direct Purchaser Settlement Agreement. On January 5, 2018, American Gypsum, New NGC, and PABCO entered into a settlement agreement (the Indirect Purchaser Settlement Agreement) with counsel representing the indirect purchaser class to settle all claims against American Gypsum, New NGC, and PABCO in the indirect purchaser class action. The Indirect Purchaser Settlement Agreement was approved by the District Court on October 26, 2018. Under the Direct and Indirect Purchaser Settlement Agreements, the Company and American Gypsum agreed to pay a total of approximately $39.1 million in cash to settle the claims against them. These claims were accrued at the time of the settlements, and during March 2018 we deposited approximately $38.8 million into a qualified settlement fund. The amount accrued under the Direct Purchaser Settlement Agreement was paid in July 2018 after approval by the District Court. In March 2015, a group of homebuilders filed a complaint against the defendants, including American Gypsum, based upon the same conduct alleged in the consolidated class action complaints. In March 2015, the Judicial Panel on Multidistrict Litigation (JPML) transferred this action to the multidistrict litigation already pending in the Eastern District of Pennsylvania. Effective May 8, 2018, American Gypsum and the homebuilder plaintiffs entered into a settlement agreement (the Homebuilder Settlement Agreement) to settle all claims made against American Gypsum. The Homebuilder Settlement Agreement, in which American Gypsum denies all wrongdoing, includes releases by the homebuilder plaintiffs of American Gypsum as well as its subsidiaries, affiliates, and other related parties, for the time period prior to and including the date of execution of the Homebuilder Settlement Agreement. Under the Homebuilder Settlement Agreement, American Gypsum agreed to pay a total of $6.0 million in cash to settle the claims against it. At March 31, 2018, we accrued the total amount of this settlement, and this amount was paid in May 2018. In June 2015, American Gypsum and an employee received grand jury subpoenas from the United States District Court for the Western District of North Carolina seeking information regarding an investigation of the gypsum drywall industry by the Antitrust Division of the Department of Justice. We believe the investigation, although a separate proceeding, was related to the same subject matter at issue in the litigation described above. On August 24, 2018, the Antitrust Division notified us that the investigation has been closed.

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	6 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	(P) FAIR VALUE OF FINANCIAL INSTRUMENTS The fair value of our long-term debt has been estimated based upon our current incremental borrowing rates for similar types of borrowing arrangements. The fair value of our Senior Unsecured Notes and Private Placement Senior Unsecured Notes at September 30, 2018 is as follows: Fair Value (dollars in thousands) Series 2007A Tranche D 37,303 4.500% Senior Unsecured Notes Due 2026 349,836 The estimated fair values were based on quoted prices of similar debt instruments with similar terms that are publicly traded (level 2 input). The carrying values of Cash and Cash Equivalents, Restricted Cash, Accounts and Notes Receivable, Accounts Payable, and Accrued Liabilities approximate their fair values at September 30, 2018 due to the short-term maturities of these assets and liabilities. The fair value of our Credit Facility also approximates its carrying value at September 30, 2018.

FINANCIAL STATEMENTS FOR GUARAN

FINANCIAL STATEMENTS FOR GUARANTORS OF THE 4.500% SENIOR UNSECURED NOTES	6 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
FINANCIAL STATEMENTS FOR GUARANTORS OF THE 4.500% SENIOR UNSECURED NOTES	(Q) FINANCIAL STATEMENTS FOR GUARANTORS OF THE 4.500% SENIOR UNSECURED NOTES On August 2, 2016, the Company completed a public offering of its Senior Unsecured Notes. The Senior Unsecured Notes are senior unsecured obligations of the Company and were offered under the Company’s existing shelf registration statement filed with the Securities and Exchange Commission. The Senior Unsecured Notes are guaranteed by all of the Company’s wholly owned subsidiaries, and all guarantees are full and unconditional, and joint and several. The following unaudited condensed consolidating financial statements present separately the Earnings and Comprehensive Earnings, Financial Position and Cash Flows of the parent issuer (Eagle Materials Inc.) and the guarantors (all wholly owned subsidiaries of Eagle Materials Inc.) on a combined basis with eliminating entries (dollars in thousands) . Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Three Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 381,499 $ — $ 381,499 Cost of Goods Sold — 283,568 — 283,568 Gross Profit — 97,931 — 97,931 Equity in Earnings of Unconsolidated Joint Venture 10,173 10,173 (10,173 ) 10,173 Equity in Earnings of Subsidiaries 75,030 — (75,030 ) — Corporate General and Administrative Expenses (9,090 ) (832 ) — (9,922 ) Legal Settlements — — — — Other Non-Operating Income (126 ) 554 — 428 Interest Expense, net (6,806 ) (11 ) — (6,817 ) Earnings before Income Taxes 69,181 107,815 (85,203 ) 91,793 Income Taxes 3,421 (22,611 ) — (19,190 ) Net Earnings $ 72,602 $ 85,204 $ (85,203 ) $ 72,603 Net Earnings $ 72,602 $ 85,204 $ (85,203 ) $ 72,603 Net Actuarial Change in Benefit Plans, net of tax 56 56 (56 ) 56 Comprehensive Earnings $ 72,658 $ 85,260 $ (85,259 ) $ 72,659 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Three Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 376,315 $ — $ 376,315 Cost of Goods Sold — 279,561 — 279,561 Gross Profit — 96,754 — 96,754 Equity in Earnings of Unconsolidated Joint Venture 11,955 11,955 (11,955 ) 11,955 Equity in Earnings of Subsidiaries 64,496 — (64,496 ) — Corporate General and Administrative Expenses (9,178 ) (643 ) — (9,821 ) Other Non-Operating Income (179 ) 1,066 — 887 Interest Expense, net (13,833 ) 6,377 — (7,456 ) Earnings before Income Taxes 53,261 115,509 (76,451 ) 92,319 Income Taxes 10,101 (39,058 ) — (28,957 ) Net Earnings $ 63,362 $ 76,451 $ (76,451 ) $ 63,362 Net Earnings $ 63,362 $ 76,451 $ (76,451 ) 63,362 Net Actuarial Change in Benefit Plans, net of tax 197 197 (197 ) 197 Comprehensive Earnings $ 63,559 $ 76,648 $ (76,648 ) $ 63,559 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Six Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 775,255 $ — $ 775,255 Cost of Goods Sold — 585,690 — 585,690 Gross Profit — 189,565 — 189,565 Equity in Earnings of Unconsolidated Joint Venture 19,424 19,424 (19,424 ) 19,424 Equity in Earnings of Subsidiaries 142,288 — (142,288 ) — Corporate General and Administrative Expenses (15,819 ) (2,106 ) — (17,925 ) Legal Settlements — (1,800 ) — (1,800 ) Other Non-Operating Income (219 ) 1,218 — 999 Interest Expense, net (13,424 ) (25 ) — (13,449 ) Earnings before Income Taxes 132,250 206,276 (161,712 ) 176,814 Income Taxes 6,692 (44,564 ) — (37,872 ) Net Earnings $ 138,942 $ 161,712 $ (161,712 ) $ 138,942 Net Earnings $ 138,942 $ 161,712 $ (161,712 ) $ 138,942 Net Actuarial Change in Benefit Plans, net of tax 112 112 (112 ) 112 Comprehensive Earnings $ 139,054 $ 161,824 $ (161,824 ) $ 139,054 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Six Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 742,436 $ — $ 742,436 Cost of Goods Sold — 559,623 — 559,623 Gross Profit — 182,813 — 182,813 Equity in Earnings of Unconsolidated Joint Venture 21,831 21,831 (21,831 ) 21,831 Equity in Earnings of Subsidiaries 122,792 — (122,792 ) — Corporate General and Administrative Expenses (17,826 ) (1,674 ) — (19,500 ) Other Non-Operating Income (346 ) 1,990 — 1,644 Interest Expense, net (26,795 ) 11,856 — (14,939 ) Earnings before Income Taxes 99,656 216,816 (144,623 ) 171,849 Income Taxes 18,588 (72,193 ) — (53,605 ) Net Earnings $ 118,244 $ 144,623 $ (144,623 ) $ 118,244 Net Earnings $ 118,244 $ 144,623 $ (144,623 ) 118,244 Net Actuarial Change in Benefit Plans, net of tax 394 394 (394 ) 394 Comprehensive Earnings $ 118,638 $ 145,017 $ (145,017 ) $ 118,638 Condensed Consolidating Balance Sheet At September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets - Cash and Cash Equivalents $ 7,584 $ 2,418 $ — $ 10,002 Restricted Cash — — — — Accounts and Notes Receivable 394 174,156 — 174,550 Inventories — 238,869 — 238,869 Income Tax Receivable 5,924 — — 5,924 Prepaid and Other Current Assets 379 7,372 — 7,751 Total Current Assets 14,281 422,815 — 437,096 Property, Plant, and Equipment - 4,521 2,631,728 — 2,636,249 Less: Accumulated Depreciation (1,167 ) (1,010,344 ) — (1,011,511 ) Property, Plant and Equipment, net 3,354 1,621,384 — 1,624,738 Notes Receivable — 3,144 — 3,144 Investment in Joint Venture 70 60,412 — 60,482 Investments in Subsidiaries and Receivables from Affiliates 2,385,185 312,633 (2,697,818 ) — Goodwill and Intangible Assets, net — 237,738 — 237,738 Other Assets 5,319 10,995 — 16,314 $ 2,408,209 $ 2,669,121 $ (2,697,818 ) $ 2,379,512 LIABILITIES AND STOCKHOLDERS’ EQUITY Current Liabilities- Accounts Payable $ 6,586 $ 85,893 $ — $ 92,479 Accrued Liabilities 19,211 43,012 — 62,223 Total Current Liabilities 25,797 128,905 — 154,702 Long-term Debt 631,257 — — 631,257 Other Long-term Liabilities 47 31,052 — 31,099 Payables to Affiliates 312,633 5,748,333 (6,060,966 ) — Deferred Income Taxes 5,872 123,979 — 129,851 Total Liabilities 975,606 6,032,269 (6,060,966 ) 946,909 Total Stockholders’ Equity 1,432,603 (3,363,148 ) 3,363,148 1,432,603 $ 2,408,209 $ 2,669,121 $ (2,697,818 ) $ 2,379,512 Condensed Consolidating Balance Sheet At March 31, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets - Cash and Cash Equivalents $ 5,784 $ 3,531 $ — $ 9,315 Restricted Cash 38,753 — — 38,753 Accounts and Notes Receivable 407 141,278 — 141,685 Inventories — 258,159 — 258,159 Income Tax Receivable 109,510 — (103,760 ) 5,750 Prepaid and Other Current Assets 665 4,408 — 5,073 Total Current Assets 155,119 407,376 (103,760 ) 458,735 Property, Plant, and Equipment - 3,188 2,583,340 — 2,586,528 Less: Accumulated Depreciation (1,089 ) (990,140 ) — (991,229 ) Property, Plant and Equipment, net 2,099 1,593,200 — 1,595,299 Notes Receivable — 115 — 115 Investment in Joint Venture 70 60,488 — 60,558 Investments in Subsidiaries and Receivables from Affiliates 2,718,809 762,340 (3,481,149 ) — Goodwill and Intangible Assets, net — 239,342 — 239,342 Other Assets 5,417 8,537 — 13,954 $ 2,881,514 $ 3,071,398 $ (3,584,909 ) $ 2,368,003 LIABILITIES AND STOCKHOLDERS’ EQUITY Current Liabilities- Accounts Payable $ 5,591 $ 67,868 $ — $ 73,459 Accrued Liabilities 67,387 38,483 — 105,870 Income Tax Payable — 103,760 (103,760 ) — Total Current Liabilities 72,978 210,111 (103,760 ) 179,329 Long-term Debt 620,922 — — 620,922 Other Long-term Liabilities 124 30,972 — 31,096 Payables to Affiliates 762,340 5,608,236 (6,370,576 ) — Deferred Income Taxes 7,460 111,506 — 118,966 Total Liabilities 1,463,824 5,960,825 (6,474,336 ) 950,313 Total Stockholders’ Equity 1,417,690 (2,889,427 ) 2,889,427 1,417,690 $ 2,881,514 $ 3,071,398 $ (3,584,909 ) $ 2,368,003 Condensed Consolidating Statement of Cash Flows For the Six Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities $ (69,161 ) $ 244,037 $ — $ 174,876 CASH FLOWS FROM INVESTING ACTIVITIES Additions to Property, Plant, and Equipment (1,133 ) (92,311 ) — (93,444 ) Proceeds from Sale of Property, Plant, and Equipment — 2,281 — 2,281 Net Cash Used in Investing Activities (1,133 ) (90,030 ) — (91,163 ) CASH FLOWS FROM FINANCING ACTIVITIES Increase in Credit Facility 10,000 — — 10,000 Dividends Paid to Stockholders (9,582 ) — — (9,582 ) Purchase and Retirement of Common Stock (122,404 ) — — (122,404 ) Proceeds from Stock Option Exercises 1,992 — — 1,992 Shares Redeemed to Settle Employee Taxes on Stock Compensation (1,785 ) — — (1,785 ) Intra-entity Activity, net 155,120 (155,120 ) — — Net Cash Provided by (Used in) Financing Activities 33,341 (155,120 ) — (121,779 ) NET INCREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH (36,953 ) (1,113 ) — (38,066 ) CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD 44,537 3,531 — 48,068 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD $ 7,584 $ 2,418 $ — $ 10,002 Condensed Consolidating Statement of Cash Flows For the Six Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities $ 21,447 $ 131,301 $ — $ 152,748 CASH FLOWS FROM INVESTING ACTIVITIES Property, Plant, and Equipment Additions — (44,851 ) — (44,851 ) Acquisition Spending — (36,761 ) — (36,761 ) Net Cash Used in Investing Activities — (81,612 ) — (81,612 ) CASH FLOWS FROM FINANCING ACTIVITIES Repayment of Credit Facility (30,000 ) — — (30,000 ) Dividends Paid to Stockholders (9,709 ) — — (9,709 ) Purchase and Retirement of Common Stock (24,903 ) — — (24,903 ) Proceeds from Stock Option Exercises 20,426 — — 20,426 Shares Redeemed to Settle Employee Taxes on Stock Compensation (2,455 ) — — (2,455 ) Intra-entity Activity, net 49,072 (49,072 ) — — Net Cash Provided by (Used in) Financing Activities 2,431 (49,072 ) — (46,641 ) NET INCREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH 23,878 617 — 24,495 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD 5,184 1,377 — 6,561 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD $ 29,062 $ 1,994 $ — $ 31,056

BASIS OF PRESENTATION (Policies

BASIS OF PRESENTATION (Policies)	6 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements RECENTLY ADOPTED In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) ASU 2014-09, “Revenue from Contracts with Customers.” ASU 2014-09 supersedes the revenue recognition requirements in “Revenue Recognition (Topic 605),” and requires entities to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. We adopted the new standard on April 1, 2018 using the modified retrospective approach. The adoption of this standard did not affect In March 2017, the FASB issued ASU 2017-07, “Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” which revises the accounting for periodic pension and postretirement expense. This ASU requires net periodic benefit cost, with the exception of service cost, to be presented retrospectively as nonoperating expense. Service cost will remain a component of Cost of Goods Sold and represent the only cost of pension and postretirement expense eligible for capitalization. We adopted the standard on April 1, 2018 using the retrospective method for presentation of service cost and other components in the income statement. We prospectively adopted the requirement to limit the capitalization of benefit cost to the service cost component. The impact of adopting this standard was not material to our financial statements . In January 2017, the FASB issued ASU 2017-04 “Simplifying the Test for Goodwill Impairment,” which eliminates the second step of the goodwill impairment test. Under the new standard, an entity should recognize an impairment charge for the amount by which the carrying value of the reporting unit exceeds the reporting unit’s fair value. This standard is effective for us in the first quarter of fiscal 2021. We adopted this standard effective April 1, 2018, and it will be effective for annual goodwill impairment tests in the fourth quarter of fiscal 2019. PENDING ADOPTION In February 2016, the FASB issued ASU 2016-02, “Leases,” which supersedes existing lease guidance to require lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by long‒term leases and to disclose additional quantitative and qualitative information about leasing arrangements. The standard will be effective for us in the first quarter of fiscal 2020, and we will adopt the standard using the modified retrospective approach. We are currently assessing the impact of the ASU on our consolidated financial statements and disclosures, as well as our internal lease accounting processes . In January 2018, the FASB issued ASU 2018-01, “Land Easement Practical Expedient for Transition to Topic 842.” This ASU permits the Company to elect not to evaluate under the new lease guidance land easements that existed or expired before the adoption of the ASU 2016-02 and that were not previously accounted for as leases. We will adopt ASU 2018-01 concurrently with the adoption of ASU 2016-02 in the first quarter of fiscal 2020.

INVENTORIES (Tables)

INVENTORIES (Tables)	6 Months Ended
	Sep. 30, 2018
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories are stated at the lower of average cost (including applicable material, labor, depreciation, and plant overhead) or net realizable value, and consist of the following: September 30, March 31, 2018 2018 (dollars in thousands) Raw Materials and Materials-in-Progress $ 105,943 $ 121,628 Finished Cement 24,003 24,089 Aggregates 7,309 7,787 Gypsum Wallboard 7,612 8,477 Paperboard 9,793 8,602 Frac Sand 2,729 1,696 Repair Parts and Supplies 76,048 79,878 Fuel and Coal 5,432 6,002 $ 238,869 $ 258,159

ACCRUED EXPENSES (Tables)

ACCRUED EXPENSES (Tables)	6 Months Ended
	Sep. 30, 2018
Payables And Accruals [Abstract]
Schedule of Accrued Expenses	Accrued Expenses consist of the following: September 30, March 31 2018 2018 (dollars in thousands) Payroll and Incentive Compensation $ 21,199 $ 25,290 Benefits 13,076 13,785 Interest 3,852 3,852 Property Taxes 8,292 5,422 Power and Fuel 1,473 1,545 Litigation Settlements 345 45,098 Rail Freight 2,012 — Legal 2,185 1,435 Sales and Use Tax 929 890 Other 8,860 8,553 $ 62,223 $ 105,870

SHARE-BASED EMPLOYEE COMPENSA_2

SHARE-BASED EMPLOYEE COMPENSATION (Tables)	6 Months Ended
	Sep. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted-Average Assumptions Used to Value Option Awards	The weighted average assumptions used in the Black-Scholes models to value the option awards in fiscal 2019 are as follows: 2018 Dividend Yield 1.3 % Expected Volatility 32.7 % Risk Free Interest Rate 2.9 % Expected Life 6.0 years
Stock Option Activity	The following table represents stock option activity for the six months ended September 30, 2018: Number of Shares Weighted Average Exercise Price Outstanding Options at Beginning of Year 958,136 $ 72.52 Granted 115,734 $ 106.14 Exercised (35,454 ) $ 110.89 Cancelled (2,197 ) $ 100.88 Outstanding Options at End of Year 1,036,219 $ 76.77 Options Exercisable at End of Year 698,207 $ 69.16 Weighted Average Fair Value of Options Granted during the Year $ 33.99
Stock Options Outstanding	The following table summarizes information about stock options outstanding at September 30, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number of Shares Outstanding Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Shares Outstanding Weighted Average Exercise Price $23.17 - $29.84 65,912 2.85 $ 23.27 65,912 $ 23.27 $33.43 - $37.34 84,582 3.71 $ 33.98 84,582 $ 33.98 $53.22 - $77.67 293,163 6.57 $ 71.27 188,311 $ 70.56 $79.73 - $106.24 592,562 7.50 $ 91.55 359,402 $ 85.12 1,036,219 6.63 $ 76.77 698,207 $ 69.16
Summary of Activity for Nonvested Restricted Shares	The fair value of restricted stock is based on the stock price at the date of grant. The following table summarizes the activity for nonvested restricted shares during the six months ended September 30, 2018: Number of Shares Weighted Average Grant Date Fair Value Restricted Stock Beginning of Year 328,059 $ 65.76 Granted 121,836 $ 105.13 Vested (46,686 ) $ 61.50 Forfeited (1,990 ) $ 100.88 Nonvested Restricted Stock at End of Year 401,219 $ 78.29

COMPUTATION OF EARNINGS PER S_2

COMPUTATION OF EARNINGS PER SHARE (Tables)	6 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Common Shares Outstanding	The calculation of basic and diluted common shares outstanding is as follows: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 Weighted Average Shares of Common Stock Outstanding 47,219,532 48,053,733 47,453,655 48,087,625 Effect of Dilutive Shares: Assumed Exercise of Outstanding Dilutive Options 785,848 1,060,209 807,861 1,159,975 Less Shares Repurchased from Proceeds of Assumed Exercised Options (588,900 ) (801,684 ) (580,350 ) (865,203 ) Restricted Stock Units 147,338 192,509 172,306 197,587 Weighted Average Common Stock and Dilutive Securities Outstanding 47,563,818 48,504,767 47,853,472 48,579,984 Shares Excluded Due to Anti-dilution Effects 181,412 88,729 163,450 76,044

PENSION AND EMPLOYEE BENEFIT _2

PENSION AND EMPLOYEE BENEFIT PLANS (Tables)	6 Months Ended
	Sep. 30, 2018
Compensation And Retirement Disclosure [Abstract]
Components of Net Periodic Cost	The following table shows the components of net periodic cost for our plans: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Service Cost - Benefits Earned During the Period $ 100 $ 153 $ 200 $ 404 Interest Cost of Projected Benefit Obligation 337 357 674 753 Expected Return on Plan Assets (463 ) (578 ) (926 ) (980 ) Recognized Net Actuarial Loss 58 46 116 473 Amortization of Prior-Service Cost 15 60 30 150 Net Periodic Pension Cost $ 47 $ 38 $ 94 $ 800

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	6 Months Ended
	Sep. 30, 2018
Debt Instrument [Line Items]
Long-Term Debt	Long-term debt consists of the following: September 30, March 31, 2018 2018 (dollars in thousands) Bank Credit Facility $ 250,000 $ 240,000 4.500% Senior Unsecured Notes Due 2026 350,000 350,000 Private Placement Senior Unsecured Notes 36,500 36,500 Total Debt 636,500 626,500 Less: Debt Origination Costs (5,243 ) (5,578 ) Long-term Debt $ 631,257 $ 620,922
Schedule of Senior Unsecured Notes Redemption Prices	Beginning on August 1, 2021, we may redeem some or all of the Senior Unsecured Notes at the redemption prices set forth below (expressed as a percentage of the principal amount being redeemed): Percentage 2021 102.25 % 2022 101.50 % 2023 100.75 % 2024 and thereafter 100.00 %
2007 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Amount Outstanding of Tranches	At September 30, 2018, the amount outstanding for the remaining tranche is as follows: Principal Maturity Date Interest Rate Tranche D $36.5 million October 2, 2019 6.48 %

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	6 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Financial Information Related to Operations by Segment	The following table sets forth certain financial information relating to our operations by segment: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Revenue - Cement $ 193,161 $ 191,650 $ 379,949 $ 374,585 Concrete and Aggregates 39,744 43,431 80,584 87,350 Gypsum Wallboard 129,609 123,068 272,024 249,881 Paperboard 41,277 45,359 86,410 89,772 Oil and Gas Proppants 19,080 22,022 40,838 40,932 Other 4,386 — 10,328 — 427,257 425,530 870,133 842,520 Less: Intersegment Revenue (20,279 ) (23,215 ) (42,135 ) (45,914 ) Less: Joint Venture Revenue (25,479 ) (26,000 ) (52,743 ) (54,170 ) $ 381,499 $ 376,315 $ 775,255 $ 742,436 For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Intersegment Revenue - Cement $ 4,073 $ 4,654 $ 8,251 $ 9,583 Concrete and Aggregates 501 402 832 815 Paperboard 15,705 18,159 33,052 35,516 $ 20,279 $ 23,215 $ 42,135 $ 45,914 Cement Sales Volume (M tons) - Wholly Owned 1,339 1,343 2,614 2,611 Joint Venture 218 227 454 470 1,557 1,570 3,068 3,081 For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Operating Earnings - Cement $ 57,547 $ 58,752 $ 94,881 $ 101,933 Concrete and Aggregates 4,100 5,619 9,584 11,640 Gypsum Wallboard 45,671 39,575 96,151 83,396 Paperboard 8,609 6,517 18,603 11,455 Oil and Gas Proppants (7,921 ) (1,754 ) (10,612 ) (3,780 ) Other 98 — 382 — Sub-Total 108,104 108,709 208,989 204,644 Corporate General and Administrative Expense (9,922 ) (9,821 ) (17,925 ) (19,500 ) Litigation Settlements and Losses — — (1,800 ) — Other Non-Operating Income 428 887 999 1,644 Earnings Before Interest and Income Taxes 98,610 99,775 190,263 186,788 Interest Expense, net (6,817 ) (7,456 ) (13,449 ) (14,939 ) Earnings Before Income Taxes $ 91,793 $ 92,319 $ 176,814 $ 171,849 Cement Operating Earnings - Wholly Owned $ 47,374 $ 46,797 $ 75,457 $ 80,102 Joint Ventures 10,173 11,955 19,424 21,831 $ 57,547 $ 58,752 $ 94,881 $ 101,933 Capital Expenditures - Cement $ 14,220 $ 13,014 $ 33,833 $ 20,732 Concrete and Aggregates 459 1,118 2,523 2,530 Gypsum Wallboard 4,124 5,219 6,479 10,861 Paperboard 5,345 659 6,410 1,423 Oil and Gas Proppants 14,827 13,781 42,463 14,360 Other, net 1,396 140 1,736 185 $ 40,371 $ 33,931 $ 93,444 $ 50,091 Depreciation, Depletion and Amortization - Cement $ 12,746 $ 12,662 $ 25,667 $ 25,141 Concrete and Aggregates 2,052 1,929 4,105 3,844 Gypsum Wallboard 5,201 4,473 10,031 8,915 Paperboard 2,128 2,172 4,237 4,309 Oil and Gas Proppants 9,398 8,518 16,537 16,124 Corporate and Other 801 552 1,599 920 $ 32,326 $ 30,306 $ 62,176 $ 59,253 September 30, March 31, 2018 2018 (dollars in thousands) Identifiable Assets Cement $ 1,274,535 $ 1,247,504 Concrete and Aggregates 104,166 104,851 Gypsum Wallboard 378,902 386,041 Paperboard 127,026 123,819 Oil and Gas Proppants 428,356 401,421 Other, net 66,527 104,367 $ 2,379,512 $ 2,368,003
Segment Breakdown of Goodwill	The segment breakdown of Goodwill is as follows: September 30, March 31, 2018 2018 (dollars in thousands) Cement $ 74,214 $ 74,214 Gypsum Wallboard 116,618 116,618 Paperboard 7,538 7,538 Corporate and Other 6,841 6,841 $ 205,211 $ 205,211
Summarized Financial Information for Joint Venture Unconsolidated	Summarized financial information for the Joint Venture that is not consolidated is set out below (this summarized financial information includes the total amount for the Joint Venture and not our 50% interest in those amounts): For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Revenue $ 51,859 $ 54,000 $ 107,510 $ 111,818 Gross Margin $ 21,877 $ 24,938 $ 42,018 $ 46,251 Earnings Before Income Taxes $ 20,345 $ 23,910 $ 38,849 $ 43,662 September 30, March 31, 2018 2018 (dollars in thousands) Current Assets $ 67,861 $ 71,089 Non-Current Assets $ 67,679 $ 66,856 Current Liabilities $ 18,191 $ 20,671

INTEREST EXPENSE (Tables)

INTEREST EXPENSE (Tables)	6 Months Ended
	Sep. 30, 2018
Banking And Thrift Interest [Abstract]
Interest Expense, Net	The following components are included in Interest Expense, net: For the Three Months Ended September 30, For the Six Months Ended September 30, 2018 2017 2018 2017 (dollars in thousands) Interest Income $ (110 ) $ (3 ) $ (112 ) $ (6 ) Interest Expense 6,660 7,153 13,002 14,329 Other Expenses 267 306 559 616 Interest Expense, net $ 6,817 $ 7,456 $ 13,449 $ 14,939

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	6 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value of Senior Notes	The fair value of our long-term debt has been estimated based upon our current incremental borrowing rates for similar types of borrowing arrangements. The fair value of our Senior Unsecured Notes and Private Placement Senior Unsecured Notes at September 30, 2018 is as follows: Fair Value (dollars in thousands) Series 2007A Tranche D 37,303 4.500% Senior Unsecured Notes Due 2026 349,836

FINANCIAL STATEMENTS FOR GUAR_2

FINANCIAL STATEMENTS FOR GUARANTORS OF THE 4.500% SENIOR UNSECURED NOTES (Tables)	6 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Condensed Consolidating Statement of Earnings and Comprehensive Earnings	Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Three Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 381,499 $ — $ 381,499 Cost of Goods Sold — 283,568 — 283,568 Gross Profit — 97,931 — 97,931 Equity in Earnings of Unconsolidated Joint Venture 10,173 10,173 (10,173 ) 10,173 Equity in Earnings of Subsidiaries 75,030 — (75,030 ) — Corporate General and Administrative Expenses (9,090 ) (832 ) — (9,922 ) Legal Settlements — — — — Other Non-Operating Income (126 ) 554 — 428 Interest Expense, net (6,806 ) (11 ) — (6,817 ) Earnings before Income Taxes 69,181 107,815 (85,203 ) 91,793 Income Taxes 3,421 (22,611 ) — (19,190 ) Net Earnings $ 72,602 $ 85,204 $ (85,203 ) $ 72,603 Net Earnings $ 72,602 $ 85,204 $ (85,203 ) $ 72,603 Net Actuarial Change in Benefit Plans, net of tax 56 56 (56 ) 56 Comprehensive Earnings $ 72,658 $ 85,260 $ (85,259 ) $ 72,659 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Three Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 376,315 $ — $ 376,315 Cost of Goods Sold — 279,561 — 279,561 Gross Profit — 96,754 — 96,754 Equity in Earnings of Unconsolidated Joint Venture 11,955 11,955 (11,955 ) 11,955 Equity in Earnings of Subsidiaries 64,496 — (64,496 ) — Corporate General and Administrative Expenses (9,178 ) (643 ) — (9,821 ) Other Non-Operating Income (179 ) 1,066 — 887 Interest Expense, net (13,833 ) 6,377 — (7,456 ) Earnings before Income Taxes 53,261 115,509 (76,451 ) 92,319 Income Taxes 10,101 (39,058 ) — (28,957 ) Net Earnings $ 63,362 $ 76,451 $ (76,451 ) $ 63,362 Net Earnings $ 63,362 $ 76,451 $ (76,451 ) 63,362 Net Actuarial Change in Benefit Plans, net of tax 197 197 (197 ) 197 Comprehensive Earnings $ 63,559 $ 76,648 $ (76,648 ) $ 63,559 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Six Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 775,255 $ — $ 775,255 Cost of Goods Sold — 585,690 — 585,690 Gross Profit — 189,565 — 189,565 Equity in Earnings of Unconsolidated Joint Venture 19,424 19,424 (19,424 ) 19,424 Equity in Earnings of Subsidiaries 142,288 — (142,288 ) — Corporate General and Administrative Expenses (15,819 ) (2,106 ) — (17,925 ) Legal Settlements — (1,800 ) — (1,800 ) Other Non-Operating Income (219 ) 1,218 — 999 Interest Expense, net (13,424 ) (25 ) — (13,449 ) Earnings before Income Taxes 132,250 206,276 (161,712 ) 176,814 Income Taxes 6,692 (44,564 ) — (37,872 ) Net Earnings $ 138,942 $ 161,712 $ (161,712 ) $ 138,942 Net Earnings $ 138,942 $ 161,712 $ (161,712 ) $ 138,942 Net Actuarial Change in Benefit Plans, net of tax 112 112 (112 ) 112 Comprehensive Earnings $ 139,054 $ 161,824 $ (161,824 ) $ 139,054 Condensed Consolidating Statement of Earnings and Comprehensive Earnings For the Six Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated Revenue $ — $ 742,436 $ — $ 742,436 Cost of Goods Sold — 559,623 — 559,623 Gross Profit — 182,813 — 182,813 Equity in Earnings of Unconsolidated Joint Venture 21,831 21,831 (21,831 ) 21,831 Equity in Earnings of Subsidiaries 122,792 — (122,792 ) — Corporate General and Administrative Expenses (17,826 ) (1,674 ) — (19,500 ) Other Non-Operating Income (346 ) 1,990 — 1,644 Interest Expense, net (26,795 ) 11,856 — (14,939 ) Earnings before Income Taxes 99,656 216,816 (144,623 ) 171,849 Income Taxes 18,588 (72,193 ) — (53,605 ) Net Earnings $ 118,244 $ 144,623 $ (144,623 ) $ 118,244 Net Earnings $ 118,244 $ 144,623 $ (144,623 ) 118,244 Net Actuarial Change in Benefit Plans, net of tax 394 394 (394 ) 394 Comprehensive Earnings $ 118,638 $ 145,017 $ (145,017 ) $ 118,638
Condensed Consolidating Balance Sheet	Condensed Consolidating Balance Sheet At September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets - Cash and Cash Equivalents $ 7,584 $ 2,418 $ — $ 10,002 Restricted Cash — — — — Accounts and Notes Receivable 394 174,156 — 174,550 Inventories — 238,869 — 238,869 Income Tax Receivable 5,924 — — 5,924 Prepaid and Other Current Assets 379 7,372 — 7,751 Total Current Assets 14,281 422,815 — 437,096 Property, Plant, and Equipment - 4,521 2,631,728 — 2,636,249 Less: Accumulated Depreciation (1,167 ) (1,010,344 ) — (1,011,511 ) Property, Plant and Equipment, net 3,354 1,621,384 — 1,624,738 Notes Receivable — 3,144 — 3,144 Investment in Joint Venture 70 60,412 — 60,482 Investments in Subsidiaries and Receivables from Affiliates 2,385,185 312,633 (2,697,818 ) — Goodwill and Intangible Assets, net — 237,738 — 237,738 Other Assets 5,319 10,995 — 16,314 $ 2,408,209 $ 2,669,121 $ (2,697,818 ) $ 2,379,512 LIABILITIES AND STOCKHOLDERS’ EQUITY Current Liabilities- Accounts Payable $ 6,586 $ 85,893 $ — $ 92,479 Accrued Liabilities 19,211 43,012 — 62,223 Total Current Liabilities 25,797 128,905 — 154,702 Long-term Debt 631,257 — — 631,257 Other Long-term Liabilities 47 31,052 — 31,099 Payables to Affiliates 312,633 5,748,333 (6,060,966 ) — Deferred Income Taxes 5,872 123,979 — 129,851 Total Liabilities 975,606 6,032,269 (6,060,966 ) 946,909 Total Stockholders’ Equity 1,432,603 (3,363,148 ) 3,363,148 1,432,603 $ 2,408,209 $ 2,669,121 $ (2,697,818 ) $ 2,379,512 Condensed Consolidating Balance Sheet At March 31, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets - Cash and Cash Equivalents $ 5,784 $ 3,531 $ — $ 9,315 Restricted Cash 38,753 — — 38,753 Accounts and Notes Receivable 407 141,278 — 141,685 Inventories — 258,159 — 258,159 Income Tax Receivable 109,510 — (103,760 ) 5,750 Prepaid and Other Current Assets 665 4,408 — 5,073 Total Current Assets 155,119 407,376 (103,760 ) 458,735 Property, Plant, and Equipment - 3,188 2,583,340 — 2,586,528 Less: Accumulated Depreciation (1,089 ) (990,140 ) — (991,229 ) Property, Plant and Equipment, net 2,099 1,593,200 — 1,595,299 Notes Receivable — 115 — 115 Investment in Joint Venture 70 60,488 — 60,558 Investments in Subsidiaries and Receivables from Affiliates 2,718,809 762,340 (3,481,149 ) — Goodwill and Intangible Assets, net — 239,342 — 239,342 Other Assets 5,417 8,537 — 13,954 $ 2,881,514 $ 3,071,398 $ (3,584,909 ) $ 2,368,003 LIABILITIES AND STOCKHOLDERS’ EQUITY Current Liabilities- Accounts Payable $ 5,591 $ 67,868 $ — $ 73,459 Accrued Liabilities 67,387 38,483 — 105,870 Income Tax Payable — 103,760 (103,760 ) — Total Current Liabilities 72,978 210,111 (103,760 ) 179,329 Long-term Debt 620,922 — — 620,922 Other Long-term Liabilities 124 30,972 — 31,096 Payables to Affiliates 762,340 5,608,236 (6,370,576 ) — Deferred Income Taxes 7,460 111,506 — 118,966 Total Liabilities 1,463,824 5,960,825 (6,474,336 ) 950,313 Total Stockholders’ Equity 1,417,690 (2,889,427 ) 2,889,427 1,417,690 $ 2,881,514 $ 3,071,398 $ (3,584,909 ) $ 2,368,003
Condensed Consolidating Statement of Cash Flows	Condensed Consolidating Statement of Cash Flows For the Six Months Ended September 30, 2018 Parent Guarantor Subsidiaries Eliminations Consolidated CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities $ (69,161 ) $ 244,037 $ — $ 174,876 CASH FLOWS FROM INVESTING ACTIVITIES Additions to Property, Plant, and Equipment (1,133 ) (92,311 ) — (93,444 ) Proceeds from Sale of Property, Plant, and Equipment — 2,281 — 2,281 Net Cash Used in Investing Activities (1,133 ) (90,030 ) — (91,163 ) CASH FLOWS FROM FINANCING ACTIVITIES Increase in Credit Facility 10,000 — — 10,000 Dividends Paid to Stockholders (9,582 ) — — (9,582 ) Purchase and Retirement of Common Stock (122,404 ) — — (122,404 ) Proceeds from Stock Option Exercises 1,992 — — 1,992 Shares Redeemed to Settle Employee Taxes on Stock Compensation (1,785 ) — — (1,785 ) Intra-entity Activity, net 155,120 (155,120 ) — — Net Cash Provided by (Used in) Financing Activities 33,341 (155,120 ) — (121,779 ) NET INCREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH (36,953 ) (1,113 ) — (38,066 ) CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD 44,537 3,531 — 48,068 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD $ 7,584 $ 2,418 $ — $ 10,002 Condensed Consolidating Statement of Cash Flows For the Six Months Ended September 30, 2017 Parent Guarantor Subsidiaries Eliminations Consolidated CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities $ 21,447 $ 131,301 $ — $ 152,748 CASH FLOWS FROM INVESTING ACTIVITIES Property, Plant, and Equipment Additions — (44,851 ) — (44,851 ) Acquisition Spending — (36,761 ) — (36,761 ) Net Cash Used in Investing Activities — (81,612 ) — (81,612 ) CASH FLOWS FROM FINANCING ACTIVITIES Repayment of Credit Facility (30,000 ) — — (30,000 ) Dividends Paid to Stockholders (9,709 ) — — (9,709 ) Purchase and Retirement of Common Stock (24,903 ) — — (24,903 ) Proceeds from Stock Option Exercises 20,426 — — 20,426 Shares Redeemed to Settle Employee Taxes on Stock Compensation (2,455 ) — — (2,455 ) Intra-entity Activity, net 49,072 (49,072 ) — — Net Cash Provided by (Used in) Financing Activities 2,431 (49,072 ) — (46,641 ) NET INCREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH 23,878 617 — 24,495 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD 5,184 1,377 — 6,561 CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD $ 29,062 $ 1,994 $ — $ 31,056

Cash Flow Information - Suppl_2

Cash Flow Information - Supplemental - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Cash payments made for interest	$ 13.9	$ 14.6
Net payments made for federal and state income taxes	$ 27.4	52.4
Non-cash investing activities related to fixed asset additions		$ 5.2

Revenue - Additional Informatio

Revenue - Additional Information (Detail)	6 Months Ended
	Sep. 30, 2018
Minimum [Member]
Supply Commitment [Line Items]
Long-term supply agreements maturity year	2,018
Revenue from contract with customer collection terms	30 days
Maximum [Member]
Supply Commitment [Line Items]
Long-term supply agreements maturity year	2,025
Revenue from contract with customer collection terms	65 days

Accounts and Notes Receivable -

Accounts and Notes Receivable - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Sep. 30, 2018	Mar. 31, 2018
Receivables [Abstract]
Allowance for doubtful accounts	$ 9.1	$ 8.6
Notes Receivable, total	3.8
Notes Receivable, current	$ 0.7
Notes Receivable interest rate	4.50%
Notes Receivable, maturity description	Remaining unpaid amounts, plus accrued interest, mature in fiscal 2025.

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - $ / shares	1 Months Ended	6 Months Ended
	Oct. 26, 2018	Sep. 30, 2018	Oct. 31, 2018
Equity Class Of Treasury Stock [Line Items]
Repurchase of shares		1,239,100
Shares repurchased average price		$ 98.77
Subsequent Event [Member]
Equity Class Of Treasury Stock [Line Items]
Repurchase of shares	300,000
Shares repurchased average price	$ 80.15
Stock repurchase remaining number of shares authorized to be repurchased			2,650,328

Schedule of Inventories (Detail

Schedule of Inventories (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Inventory [Line Items]
Inventories	$ 238,869	$ 258,159
Raw Materials and Material-in-Progress [Member]
Inventory [Line Items]
Inventories	105,943	121,628
Finished Cement [Member]
Inventory [Line Items]
Inventories	24,003	24,089
Aggregates [Member]
Inventory [Line Items]
Inventories	7,309	7,787
Gypsum Wallboard [Member]
Inventory [Line Items]
Inventories	7,612	8,477
Paperboard [Member]
Inventory [Line Items]
Inventories	9,793	8,602
Frac Sand [Member]
Inventory [Line Items]
Inventories	2,729	1,696
Repair Parts and Supplies [Member]
Inventory [Line Items]
Inventories	76,048	79,878
Fuel and Coal [Member]
Inventory [Line Items]
Inventories	$ 5,432	$ 6,002

Schedule of Accrued Expenses (D

Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Accounts Payable And Accrued Liabilities Current [Abstract]
Payroll and Incentive Compensation	$ 21,199	$ 25,290
Benefits	13,076	13,785
Interest	3,852	3,852
Property Taxes	8,292	5,422
Power and Fuel	1,473	1,545
Litigation Settlements	345	45,098
Rail Freight	2,012
Legal	2,185	1,435
Sales and Use Tax	929	890
Other	8,860	8,553
Accrued Expenses, Total	$ 62,223	$ 105,870

Share-Based Employee Compensa_3

Share-Based Employee Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Aug. 31, 2018	May 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Aug. 07, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant			3,984,117		3,984,117		3,000,000
Stock option expense			$ 1	$ 1.3	$ 2.1	$ 2.2
Aggregate intrinsic value for outstanding options			8.8		8.8
Aggregate intrinsic value of exercisable options			11.2		11.2
Total intrinsic value of options exercised					1.9
Restricted stock or unit expense			3.1	$ 2.5	$ 5.5	$ 5
Stock Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant							1,500,000
Performance Vesting Stock Options [Member] | Long Term Compensation Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		62,179
Reduced percentage of shares earned in stock options plan					66.70%
Stock based compensation plan, description					The performance criteria for the Fiscal 2019 Employee Performance Stock Option Grant is based upon the achievement of certain levels of return on equity (as defined in the option agreements), ranging from 10.0% to 20.0%, for the fiscal year ending March 31, 2019. All stock options will be earned if the return on equity is 20.0% or greater, and the percentage of shares earned will be reduced proportionately to approximately 66.7% if the return on equity is 10.0%. If the Company does not achieve a return on equity of at least 10.0%, all stock options granted will be forfeited.
Share-based compensation vesting period		4 years
Share-based compensation award expiration term		10 years
Performance Vesting Stock Options [Member] | Long Term Compensation Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of average return on invested capital		10.00%
Share-based compensation expiration date					Mar. 31, 2019
Performance Vesting Stock Options [Member] | Long Term Compensation Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of average return on invested capital		20.00%
Share-based compensation expiration date					Mar. 31, 2022
Time Vesting Stock Options [Member] | Long Term Compensation Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		51,814
Share-based compensation vesting period		4 years
Board of Directors Stock Option [Member] | Long Term Compensation Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant	1,741
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost, stock options			8.5		$ 8.5
Weighted-average period of recognition of unrecognized compensation cost					2 years 8 months 12 days
Performance Vesting Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		57,756
Stock based compensation plan, description					The performance criteria for the Fiscal 2019 Employee Restricted Stock Performance Award is based upon the achievement of certain levels of return on equity (as defined in the award agreement), ranging from 10.0% to 20.0%, for the fiscal year ending March 31, 2019. All restricted shares will be earned if the return on equity is 20.0% or greater, and the percentage of shares earned will be reduced proportionately to approximately 66.7% if the return on equity is 10.0%. If the Company does not achieve a return on equity of at least 10.0%, all awards will be forfeited.
Share-based compensation vesting period		4 years
Reduced percentage of restricted shares					66.70%
Performance Vesting Restricted Stock [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of average return on invested capital		10.00%
Share-based compensation vesting date					Mar. 31, 2020
Performance Vesting Restricted Stock [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of average return on invested capital		20.00%
Share-based compensation vesting date					Mar. 31, 2022
Time Vesting Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant		48,130
Share-based compensation vesting period		4 years
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant	15,950
Share-based compensation vesting period	6 months
Weighted-average period of recognition of unrecognized compensation cost					2 years 4 months 24 days
Weighted average grant date fair value, shares granted					$ 105.13
Unrecognized compensation cost			$ 24.5		$ 24.5

Weighted-Average Assumptions Us

Weighted-Average Assumptions Used to Value Option Awards (Detail) - Long Term Compensation Plan [Member] - Stock Options [Member]	6 Months Ended
	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend Yield	1.30%
Expected Volatility	32.70%
Risk Free Interest Rate	2.90%
Expected Life	6 years

Stock Option Activity (Detail)

Stock Option Activity (Detail)	6 Months Ended
	Sep. 30, 2018$ / sharesshares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Outstanding Options at Beginning of Year | shares	958,136
Number of Shares, Granted | shares	115,734
Number of Shares, Exercised | shares	(35,454)
Number of Shares, Cancelled | shares	(2,197)
Number of Shares, Outstanding Options at End of Year | shares	1,036,219
Number of Shares, Options Exercisable at End of Year | shares	698,207
Weighted-Average Exercise Price, Outstanding Options at Beginning of Year	$ 72.52
Weighted-Average Exercise Price, Granted	106.14
Weighted-Average Exercise Price, Exercised	110.89
Weighted-Average Exercise Price, Cancelled	100.88
Weighted-Average Exercise Price, Outstanding Options at End of Year	76.77
Weighted-Average Exercise Price, Options Exercisable at End of Period	69.16
Weighted Average Fair Value of Options Granted during the Year	$ 33.99

Stock Options Outstanding (Deta

Stock Options Outstanding (Detail)	6 Months Ended
	Sep. 30, 2018$ / sharesshares
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Options Outstanding, Number of Shares Outstanding | shares	1,036,219
Options Outstanding, Weighted-Average Remaining Contractual Life	6 years 7 months 17 days
Options Outstanding, Weighted-Average Exercise Price	$ 76.77
Options Exercisable , Number of Shares Outstanding | shares	698,207
Options Exercisable, Weighted-Average Exercise Price	$ 69.16
$23.17 - $29.84 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	23.17
Range of Exercise Prices, Upper Range	$ 29.84
Options Outstanding, Number of Shares Outstanding | shares	65,912
Options Outstanding, Weighted-Average Remaining Contractual Life	2 years 10 months 6 days
Options Outstanding, Weighted-Average Exercise Price	$ 23.27
Options Exercisable , Number of Shares Outstanding | shares	65,912
Options Exercisable, Weighted-Average Exercise Price	$ 23.27
$33.43 - $ 37.34 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	33.43
Range of Exercise Prices, Upper Range	$ 37.34
Options Outstanding, Number of Shares Outstanding | shares	84,582
Options Outstanding, Weighted-Average Remaining Contractual Life	3 years 8 months 15 days
Options Outstanding, Weighted-Average Exercise Price	$ 33.98
Options Exercisable , Number of Shares Outstanding | shares	84,582
Options Exercisable, Weighted-Average Exercise Price	$ 33.98
$53.22 - $ 77.67 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	53.22
Range of Exercise Prices, Upper Range	$ 77.67
Options Outstanding, Number of Shares Outstanding | shares	293,163
Options Outstanding, Weighted-Average Remaining Contractual Life	6 years 6 months 25 days
Options Outstanding, Weighted-Average Exercise Price	$ 71.27
Options Exercisable , Number of Shares Outstanding | shares	188,311
Options Exercisable, Weighted-Average Exercise Price	$ 70.56
$79.73 - $ 106.24 [Member]
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	79.73
Range of Exercise Prices, Upper Range	$ 106.24
Options Outstanding, Number of Shares Outstanding | shares	592,562
Options Outstanding, Weighted-Average Remaining Contractual Life	7 years 6 months
Options Outstanding, Weighted-Average Exercise Price	$ 91.55
Options Exercisable , Number of Shares Outstanding | shares	359,402
Options Exercisable, Weighted-Average Exercise Price	$ 85.12

Summary of Activity for Nonvest

Summary of Activity for Nonvested Restricted Shares (Detail) - Restricted Stock [Member]	6 Months Ended
	Sep. 30, 2018$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Beginning of Year | shares	328,059
Number of Shares, Granted | shares	121,836
Number of Shares, Vested | shares	(46,686)
Number of Shares, Forfeited | shares	(1,990)
Number of Shares, Nonvested at End of Year | shares	401,219
Weighted Average Grant Date Fair Value, Beginning of Year | $ / shares	$ 65.76
Weighted Average Grant Date Fair Value, Granted | $ / shares	105.13
Weighted Average Grant Date Fair Value, Vested | $ / shares	61.50
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	100.88
Weighted Average Grant Date Fair Value, Nonvested at End of Year | $ / shares	$ 78.29

Calculation of Basic and Dilute

Calculation of Basic and Diluted Common Shares Outstanding (Detail) - shares	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Weighted Average Shares of Common Stock Outstanding	47,219,532	48,053,733	47,453,655	48,087,625
Assumed Exercise of Outstanding Dilutive Options	785,848	1,060,209	807,861	1,159,975
Less Shares Repurchased from Proceeds of Assumed Exercised Options	(588,900)	(801,684)	(580,350)	(865,203)
Restricted Stock Units	147,338	192,509	172,306	197,587
Weighted Average Common Stock and Dilutive Securities Outstanding	47,563,818	48,504,767	47,853,472	48,579,984
Shares Excluded Due to Anti-dilution Effects	181,412	88,729	163,450	76,044

Components of Net Periodic Cost

Components of Net Periodic Cost (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Compensation And Retirement Disclosure [Abstract]
Service Cost - Benefits Earned During the Period	$ 100	$ 153	$ 200	$ 404
Interest Cost of Projected Benefit Obligation	337	357	674	753
Expected Return on Plan Assets	(463)	(578)	(926)	(980)
Recognized Net Actuarial Loss	58	46	116	473
Amortization of Prior-Service Cost	15	60	30	150
Net Periodic Pension Cost	$ 47	$ 38	$ 94	$ 800

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	6 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal corporate tax rate			21.00%	35.00%
Deductibility percentage of certain capital expenditures			100.00%
Tax rate	21.00%	31.00%

Long-Term Debt (Detail)

Long-Term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018	Aug. 02, 2016
Debt Instrument [Line Items]
Bank Credit Facility	$ 250,000	$ 240,000
Total Debt	636,500	626,500
Less: Debt Origination Costs	(5,243)	(5,578)
Long-term Debt	631,257	620,922
4.500% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Total Debt	350,000	350,000	$ 350,000
Private Placement Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Total Debt	$ 36,500	$ 36,500

Long-Term Debt (Parenthetical)

Long-Term Debt (Parenthetical) (Detail) - 4.500% Senior Unsecured Notes Due 2026 [Member]	6 Months Ended
	Sep. 30, 2018	Aug. 02, 2016
Debt Instrument [Line Items]
Debt instrument, interest rate	4.50%	4.50%
Debt instrument, maturity year	2,026

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail)	Aug. 02, 2016USD ($)	Oct. 31, 2014	Sep. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Oct. 02, 2007USD ($)Loan
Debt Instrument [Line Items]
Interest coverage ratio		250.00%
Unused line of credit commitment fee based on leverage ratio		0.10%
Borrowings outstanding under Credit Facility			$ 250,000,000	$ 240,000,000
Bank Credit Facility, borrowings available			242,200,000
Letter of Credit Facility			40,000,000
Outstanding letters of credit , amount			7,800,000
Debt instrument, principal amount			636,500,000	626,500,000
Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio		350.00%
Unused line of credit commitment fee based on leverage ratio		0.35%
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Variable margin		1.00%
London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Variable margin		2.25%
Federal Funds Effective Swap Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Variable margin		0.00%
Federal Funds Effective Swap Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Variable margin		1.25%
4.500% Senior Unsecured Notes Due 2026 [Member]
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 350,000,000		$ 350,000,000	$ 350,000,000
Debt instrument, interest rate	4.50%		4.50%
Debt instrument, maturity period	2026-08
4.500% Senior Unsecured Notes Due 2026 [Member] | Prior to August 1, 2019 [Member]
Debt Instrument [Line Items]
Redemption price, percentage	104.50%
4.500% Senior Unsecured Notes Due 2026 [Member] | On or After August 1, 2019 and Prior to August 1, 2021 [Member]
Debt Instrument [Line Items]
Redemption price, percentage	100.00%
4.500% Senior Unsecured Notes Due 2026 [Member] | Maximum [Member] | Prior to August 1, 2019 [Member]
Debt Instrument [Line Items]
Percentage of principal amount redeemable	40.00%
2007 Note Purchase Agreement [Member]
Debt Instrument [Line Items]
Interest coverage ratio			250.00%
Number of tranches | Loan					4
Senior Notes, sale					$ 200,000,000
Senior Notes, payment terms			Interest for the Series 2007A Senior Unsecured Notes is payable semi-annually April 2 and October 2 of each year until all principal is paid for the respective tranche.
Purchase agreement additional requirements			and to maintain an interest coverage ratio (Consolidated EBITDA to Consolidated Interest Expense [calculated as consolidated EBITDA, as defined above, to consolidated interest expense]) of at least 2.50:1.00. In addition, the 2007 Note Purchase Agreement requires the Company to ensure that at all times either (i) Consolidated Total Assets equal at least 80% of the consolidated total assets of the Company and its subsidiaries, determined in accordance with GAAP; or (ii) consolidated Total Revenue of the Company and its restricted subsidiaries for the period of four consecutive fiscal quarters most recently ended equals at least 80% of the consolidated Total Revenue of the Company and its Subsidiaries during such period.
Senior Notes, permitted minimum aggregate principal amount prepayment without penalty			10.00%
Percentage of face value to be paid if notes are prepaid			100.00%
Senior Notes, calculation of make-whole amount, description			Discounting the remaining scheduled principal and interest payments at a discount rate of 50 basis
Discount on Senior Notes principal and interest			0.50%
2007 Note Purchase Agreement [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of consolidated assets require to maintain			80.00%
Percentage of consolidated revenues require to maintain			80.00%
2007 Note Purchase Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Consolidated funded indebtedness ratio			350.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Facility, principal balance			$ 500,000,000
Credit Facility, termination date			Aug. 2, 2021
Credit Facility, interest rate description			At our option, outstanding principal amounts on the Credit Facility bear interest at a variable rate equal to (i) the London Interbank Offered Rate (LIBOR) plus an agreed margin (ranging from 100 to 225 basis points), which is to be established quarterly based upon the Company’s ratio of consolidated EBITDA, defined as earnings before interest, taxes, depreciation, and amortization, to the Company’s consolidated indebtedness (the Leverage Ratio); or (ii) an alternative base rate which is the higher of (a) the prime rate or (b) the federal funds rate plus 1⁄2% per annum plus an applicable rate (ranging from 0 to 125 basis points). In the case of loans bearing interest at a rate based on the federal funds rate, interest is payable quarterly. In the case of loans bearing interest at a rate based on LIBOR, interest is payable at the end of the LIBOR advance periods, which can be up to nine months at the option of the Company. The Company is also required to pay a commitment fee on unused available borrowings under the Credit Facility ranging from 10 to 35 basis points depending upon the Leverage Ratio.
Revolving Credit Facility [Member] | Swingline Loan [Member]
Debt Instrument [Line Items]
Credit Facility, principal balance			$ 25,000,000
Line of Credit | Federal Funds Effective Swap Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Variable margin		0.50%
Letter of Credit [Member]
Debt Instrument [Line Items]
Bank Credit Facility, one-time fee			0.125%

Schedule of Senior Unsecured No

Schedule of Senior Unsecured Notes Redemption Prices (Detail) - 4.500% Senior Unsecured Notes Due 2026 [Member]	6 Months Ended
	Sep. 30, 2018
2021 [Member]
Debt Instrument Redemption [Line Items]
Redemption price, percentage	102.25%
2022 [Member]
Debt Instrument Redemption [Line Items]
Redemption price, percentage	101.50%
2023 [Member]
Debt Instrument Redemption [Line Items]
Redemption price, percentage	100.75%
2024 and Thereafter [Member]
Debt Instrument Redemption [Line Items]
Redemption price, percentage	100.00%

Amount Outstanding of Tranches

Amount Outstanding of Tranches - Two Thousand Seven Note Purchase Agreement (Detail) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Principal	$ 636,500	$ 626,500
2007 Note Purchase Agreement [Member] | Series 2007A Tranche D [Member]
Debt Instrument [Line Items]
Principal	$ 36,500
Maturity Date	Oct. 2, 2019
Interest Rate	6.48%

Segment Information - Additiona

Segment Information - Additional Information (Detail)	6 Months Ended
	Sep. 30, 2018LocationFacilityTerminalPlantSectorSegmentJointVentures
Segment Reporting Information [Line Items]
Number of sectors | Sector	3
Number of reportable business segments | Segment	5
Cement plant locations | Location	7
Slag grinding facility | Facility	1
Cement distribution terminals | Terminal	18
Gypsum wallboard plants | Plant	5
Readymix concrete batch plants | Plant	17
Aggregates processing plants | 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
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

Financial Information Related t

Financial Information Related to Operations by Segment (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018USD ($)kT	Sep. 30, 2017USD ($)kT	Sep. 30, 2018USD ($)kT	Sep. 30, 2017USD ($)kT	Mar. 31, 2018USD ($)
Segment Reporting Information [Line Items]
Revenue	$ 381,499	$ 376,315	$ 775,255	$ 742,436
Less: Joint Venture Revenue	(25,479)	(26,000)	(52,743)	(54,170)
Operating Earnings	108,104	108,709	208,989	204,644
Corporate General and Administrative Expense	(9,922)	(9,821)	(17,925)	(19,500)
Litigation Settlements and Losses			(1,800)
Other Non-Operating Income	428	887	999	1,644
Earnings Before Interest and Income Taxes	98,610	99,775	190,263	186,788
Interest Expense, Net	(6,817)	(7,456)	(13,449)	(14,939)
Earnings before Income Taxes	91,793	92,319	176,814	171,849
Capital Expenditures	40,371	33,931	93,444	50,091
Depreciation, Depletion and Amortization	32,326	30,306	62,176	59,253
Identifiable Assets	2,379,512		2,379,512		$ 2,368,003
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	427,257	425,530	870,133	842,520
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(20,279)	(23,215)	(42,135)	(45,914)
Other [Member]
Segment Reporting Information [Line Items]
Operating Earnings	98		382
Capital Expenditures	1,396	140	1,736	185
Identifiable Assets	66,527		66,527		104,367
Cement [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	$ 193,161	$ 191,650	$ 379,949	$ 374,585
Cement Sales Volume | kT	1,557	1,570	3,068	3,081
Operating Earnings	$ 57,547	$ 58,752	$ 94,881	$ 101,933
Capital Expenditures	14,220	13,014	33,833	20,732
Depreciation, Depletion and Amortization	12,746	$ 12,662	25,667	$ 25,141
Identifiable Assets	$ 1,274,535		$ 1,274,535		1,247,504
Cement [Member] | Operating Segments [Member] | Wholly-Owned [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume | kT	1,339	1,343	2,614	2,611
Operating Earnings	$ 47,374	$ 46,797	$ 75,457	$ 80,102
Cement [Member] | Operating Segments [Member] | Joint Venture [Member]
Segment Reporting Information [Line Items]
Cement Sales Volume | kT	218	227	454	470
Operating Earnings	$ 10,173	$ 11,955	$ 19,424	$ 21,831
Cement [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(4,073)	(4,654)	(8,251)	(9,583)
Concrete and Aggregates [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	39,744	43,431	80,584	87,350
Operating Earnings	4,100	5,619	9,584	11,640
Capital Expenditures	459	1,118	2,523	2,530
Depreciation, Depletion and Amortization	2,052	1,929	4,105	3,844
Identifiable Assets	104,166		104,166		104,851
Concrete and Aggregates [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(501)	(402)	(832)	(815)
Gypsum Wallboard [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	129,609	123,068	272,024	249,881
Operating Earnings	45,671	39,575	96,151	83,396
Capital Expenditures	4,124	5,219	6,479	10,861
Depreciation, Depletion and Amortization	5,201	4,473	10,031	8,915
Identifiable Assets	378,902		378,902		386,041
Paperboard [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	41,277	45,359	86,410	89,772
Operating Earnings	8,609	6,517	18,603	11,455
Capital Expenditures	5,345	659	6,410	1,423
Depreciation, Depletion and Amortization	2,128	2,172	4,237	4,309
Identifiable Assets	127,026		127,026		123,819
Paperboard [Member] | Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenue	(15,705)	(18,159)	(33,052)	(35,516)
Oil and Gas Proppants [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	19,080	22,022	40,838	40,932
Operating Earnings	(7,921)	(1,754)	(10,612)	(3,780)
Capital Expenditures	14,827	13,781	42,463	14,360
Depreciation, Depletion and Amortization	9,398	8,518	16,537	16,124
Identifiable Assets	428,356		428,356		$ 401,421
Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue	4,386		10,328
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization	$ 801	$ 552	$ 1,599	$ 920

Segment Breakdown of Goodwill (

Segment Breakdown of Goodwill (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Segment Reporting Information [Line Items]
Goodwill	$ 205,211	$ 205,211
Cement [Member]
Segment Reporting Information [Line Items]
Goodwill	74,214	74,214
Gypsum Wallboard [Member]
Segment Reporting Information [Line Items]
Goodwill	116,618	116,618
Paperboard [Member]
Segment Reporting Information [Line Items]
Goodwill	7,538	7,538
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 6,841	$ 6,841

Summarized Financial Informatio

Summarized Financial Information for Joint Venture Unconsolidated (Detail) - Joint Venture [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018
Related Party Transaction [Line Items]
Revenue	$ 51,859	$ 54,000	$ 107,510	$ 111,818
Gross Margin	21,877	24,938	42,018	46,251
Earnings Before Income Taxes	20,345	$ 23,910	38,849	$ 43,662
Current Assets	67,861		67,861		$ 71,089
Non-Current Assets	67,679		67,679		66,856
Current Liabilities	$ 18,191		$ 18,191		$ 20,671

Interest Expense, Net (Detail)

Interest Expense, Net (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest Income (Expense), Net [Abstract]
Interest Income	$ (110)	$ (3)	$ (112)	$ (6)
Interest Expense	6,660	7,153	13,002	14,329
Other Expenses	267	306	559	616
Interest Expense, net	$ 6,817	$ 7,456	$ 13,449	$ 14,939

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	May 08, 2018	Jan. 05, 2018	Mar. 31, 2018	Sep. 30, 2018
Commitments And Contingencies [Line Items]
Letters of credit outstanding, amount				$ 7,800,000
Outstanding guarantees				0
Contingently liable for performance, current				$ 27,700,000
American Gypsum Company LLC [Member] | Homebuilder Settlement Agreement [Member]
Commitments And Contingencies [Line Items]
Litigation settlement amount	$ 6,000,000
American Gypsum Company LLC [Member] | Direct and Indirect Purchaser Class [Member] | Direct and Indirect Purchaser Settlement Agreements [Member]
Commitments And Contingencies [Line Items]
Litigation settlement amount		$ 39,100,000
Amount deposited to qualified settlement fund			$ 38,800,000

Fair Value of Senior Notes (Det

Fair Value of Senior Notes (Detail) $ in Thousands	Sep. 30, 2018USD ($)
Series 2007A Tranche D [Member]
Fair Value Of Financial Instruments [Line Items]
Fair Value of Senior Notes	$ 37,303
4.500% Senior Unsecured Notes Due 2026 [Member]
Fair Value Of Financial Instruments [Line Items]
Fair Value of Senior Notes	$ 349,836

Fair Value of Senior Notes (Par

Fair Value of Senior Notes (Parenthetical) (Detail) - 4.500% Senior Unsecured Notes Due 2026 [Member]	6 Months Ended
	Sep. 30, 2018	Aug. 02, 2016
Fair Value Of Financial Instruments [Line Items]
Debt instrument, interest rate	4.50%	4.50%
Debt instrument, maturity year	2,026

Condensed Consolidating Stateme

Condensed Consolidating Statement of Earnings and Comprehensive Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 31, 2018
Revenue	$ 381,499	$ 376,315	$ 775,255	$ 742,436
Cost of Goods Sold	283,568	279,561	585,690	559,623
Gross Profit	97,931	96,754	189,565	182,813
Equity in Earnings of Unconsolidated Joint Venture	10,173	11,955	19,424	21,831
Corporate General and Administrative Expense	(9,922)	(9,821)	(17,925)	(19,500)
Legal Settlements			(1,800)
Other Non-Operating Income	428	887	999	1,644
Interest Expense, net	(6,817)	(7,456)	(13,449)	(14,939)
Earnings before Income Taxes	91,793	92,319	176,814	171,849
Income Taxes	(19,190)	(28,957)	(37,872)	(53,605)
Net Earnings	72,603	63,362	138,942	118,244	$ 256,632
Net Actuarial Change in Benefit Plans, net of tax	56	197	112	394
Comprehensive Earnings	72,659	63,559	139,054	118,638
Eliminations [Member]
Equity in Earnings of Unconsolidated Joint Venture	(10,173)	(11,955)	(19,424)	(21,831)
Equity in Earnings of Subsidiaries	(75,030)	(64,496)	(142,288)	(122,792)
Earnings before Income Taxes	(85,203)	(76,451)	(161,712)	(144,623)
Net Earnings	(85,203)	(76,451)	(161,712)	(144,623)
Net Actuarial Change in Benefit Plans, net of tax	(56)	(197)	(112)	(394)
Comprehensive Earnings	(85,259)	(76,648)	(161,824)	(145,017)
Parent [Member]
Equity in Earnings of Unconsolidated Joint Venture	10,173	11,955	19,424	21,831
Equity in Earnings of Subsidiaries	75,030	64,496	142,288	122,792
Corporate General and Administrative Expense	(9,090)	(9,178)	(15,819)	(17,826)
Other Non-Operating Income	(126)	(179)	(219)	(346)
Interest Expense, net	(6,806)	(13,833)	(13,424)	(26,795)
Earnings before Income Taxes	69,181	53,261	132,250	99,656
Income Taxes	3,421	10,101	6,692	18,588
Net Earnings	72,602	63,362	138,942	118,244
Net Actuarial Change in Benefit Plans, net of tax	56	197	112	394
Comprehensive Earnings	72,658	63,559	139,054	118,638
Guarantor Subsidiaries [Member]
Revenue	381,499	376,315	775,255	742,436
Cost of Goods Sold	283,568	279,561	585,690	559,623
Gross Profit	97,931	96,754	189,565	182,813
Equity in Earnings of Unconsolidated Joint Venture	10,173	11,955	19,424	21,831
Corporate General and Administrative Expense	(832)	(643)	(2,106)	(1,674)
Legal Settlements			(1,800)
Other Non-Operating Income	554	1,066	1,218	1,990
Interest Expense, net	(11)	6,377	(25)	11,856
Earnings before Income Taxes	107,815	115,509	206,276	216,816
Income Taxes	(22,611)	(39,058)	(44,564)	(72,193)
Net Earnings	85,204	76,451	161,712	144,623
Net Actuarial Change in Benefit Plans, net of tax	56	197	112	394
Comprehensive Earnings	$ 85,260	$ 76,648	$ 161,824	$ 145,017

Condensed Consolidating Balance

Condensed Consolidating Balance Sheet (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018	Mar. 31, 2017
Current Assets -
Cash and Cash Equivalents	$ 10,002	$ 9,315
Restricted Cash		38,753
Accounts and Notes Receivable	174,550	141,685
Inventories	238,869	258,159
Income Tax Receivable	5,924	5,750
Prepaid and Other Current Assets	7,751	5,073
Total Current Assets	437,096	458,735
Property, Plant, and Equipment -	2,636,249	2,586,528
Less: Accumulated Depreciation	(1,011,511)	(991,229)
Property, Plant, and Equipment, net	1,624,738	1,595,299
Notes Receivable	3,144	115
Investment in Joint Venture	60,482	60,558
Goodwill and Intangible Assets, net	237,738	239,342
Other Assets	16,314	13,954
Total Assets	2,379,512	2,368,003
Current Liabilities -
Accounts Payable	92,479	73,459
Accrued Liabilities	62,223	105,870
Total Current Liabilities	154,702	179,329
Long-term Debt	631,257	620,922
Other Long-term Liabilities	31,099	31,096
Deferred Income Taxes	129,851	118,966
Total Liabilities	946,909	950,313
Total Stockholders’ Equity	1,432,603	1,417,690	$ 1,203,450
Liabilities and Stockholders' Equity, Total	2,379,512	2,368,003
Eliminations [Member]
Current Assets -
Income Tax Receivable		(103,760)
Total Current Assets		(103,760)
Investments in Subsidiaries and Receivables from Affiliates	(2,697,818)	(3,481,149)
Total Assets	(2,697,818)	(3,584,909)
Current Liabilities -
Income Tax Payable		(103,760)
Total Current Liabilities		(103,760)
Payables to Affiliates	(6,060,966)	(6,370,576)
Total Liabilities	(6,060,966)	(6,474,336)
Total Stockholders’ Equity	3,363,148	2,889,427
Liabilities and Stockholders' Equity, Total	(2,697,818)	(3,584,909)
Parent [Member]
Current Assets -
Cash and Cash Equivalents	7,584	5,784
Restricted Cash		38,753
Accounts and Notes Receivable	394	407
Income Tax Receivable	5,924	109,510
Prepaid and Other Current Assets	379	665
Total Current Assets	14,281	155,119
Property, Plant, and Equipment -	4,521	3,188
Less: Accumulated Depreciation	(1,167)	(1,089)
Property, Plant, and Equipment, net	3,354	2,099
Investment in Joint Venture	70	70
Investments in Subsidiaries and Receivables from Affiliates	2,385,185	2,718,809
Other Assets	5,319	5,417
Total Assets	2,408,209	2,881,514
Current Liabilities -
Accounts Payable	6,586	5,591
Accrued Liabilities	19,211	67,387
Total Current Liabilities	25,797	72,978
Long-term Debt	631,257	620,922
Other Long-term Liabilities	47	124
Payables to Affiliates	312,633	762,340
Deferred Income Taxes	5,872	7,460
Total Liabilities	975,606	1,463,824
Total Stockholders’ Equity	1,432,603	1,417,690
Liabilities and Stockholders' Equity, Total	2,408,209	2,881,514
Guarantor Subsidiaries [Member]
Current Assets -
Cash and Cash Equivalents	2,418	3,531
Accounts and Notes Receivable	174,156	141,278
Inventories	238,869	258,159
Prepaid and Other Current Assets	7,372	4,408
Total Current Assets	422,815	407,376
Property, Plant, and Equipment -	2,631,728	2,583,340
Less: Accumulated Depreciation	(1,010,344)	(990,140)
Property, Plant, and Equipment, net	1,621,384	1,593,200
Notes Receivable	3,144	115
Investment in Joint Venture	60,412	60,488
Investments in Subsidiaries and Receivables from Affiliates	312,633	762,340
Goodwill and Intangible Assets, net	237,738	239,342
Other Assets	10,995	8,537
Total Assets	2,669,121	3,071,398
Current Liabilities -
Accounts Payable	85,893	67,868
Accrued Liabilities	43,012	38,483
Income Tax Payable		103,760
Total Current Liabilities	128,905	210,111
Other Long-term Liabilities	31,052	30,972
Payables to Affiliates	5,748,333	5,608,236
Deferred Income Taxes	123,979	111,506
Total Liabilities	6,032,269	5,960,825
Total Stockholders’ Equity	(3,363,148)	(2,889,427)
Liabilities and Stockholders' Equity, Total	$ 2,669,121	$ 3,071,398

Condensed Consolidating State_2

Condensed Consolidating Statement of Cash Flows (Detail) - USD ($) $ in Thousands	6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net Cash Provided by (Used in) Operating Activities	$ 174,876	$ 152,748
CASH FLOWS FROM INVESTING ACTIVITIES
Additions to Property, Plant, and Equipment	(93,444)	(44,851)
Proceeds from Sale of Property, Plant, and Equipment	2,281
Acquisition Spending		(36,761)
Net Cash Used in Investing Activities	(91,163)	(81,612)
CASH FLOWS FROM FINANCING ACTIVITIES
Increase (Repayment) of Credit Facility	10,000	(30,000)
Dividends Paid to Stockholders	(9,582)	(9,709)
Purchase and Retirement of Common Stock	(122,404)	(24,903)
Proceeds from Stock Option Exercises	1,992	20,426
Shares Redeemed to Settle Employee Taxes on Stock Compensation	(1,785)	(2,455)
Net Cash Used in Financing Activities	(121,779)	(46,641)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	(38,066)	24,495
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	48,068	6,561
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	10,002	31,056
Parent [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Cash Provided by (Used in) Operating Activities	(69,161)	21,447
CASH FLOWS FROM INVESTING ACTIVITIES
Additions to Property, Plant, and Equipment	(1,133)
Net Cash Used in Investing Activities	(1,133)
CASH FLOWS FROM FINANCING ACTIVITIES
Increase (Repayment) of Credit Facility	10,000	(30,000)
Dividends Paid to Stockholders	(9,582)	(9,709)
Purchase and Retirement of Common Stock	(122,404)	(24,903)
Proceeds from Stock Option Exercises	1,992	20,426
Shares Redeemed to Settle Employee Taxes on Stock Compensation	(1,785)	(2,455)
Intra-entity Activity, net	155,120	49,072
Net Cash Used in Financing Activities	33,341	2,431
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	(36,953)	23,878
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	44,537	5,184
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	7,584	29,062
Guarantor Subsidiaries [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net Cash Provided by (Used in) Operating Activities	244,037	131,301
CASH FLOWS FROM INVESTING ACTIVITIES
Additions to Property, Plant, and Equipment	(92,311)	(44,851)
Proceeds from Sale of Property, Plant, and Equipment	2,281
Acquisition Spending		(36,761)
Net Cash Used in Investing Activities	(90,030)	(81,612)
CASH FLOWS FROM FINANCING ACTIVITIES
Intra-entity Activity, net	(155,120)	(49,072)
Net Cash Used in Financing Activities	(155,120)	(49,072)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	(1,113)	617
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF PERIOD	3,531	1,377
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD	$ 2,418	$ 1,994