Condensed Consolidating Statement of Earnings and Comprehensive Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Revenue	$ 370,597	$ 393,756
Cost of Goods Sold	295,268	302,122
Gross Profit	75,329	91,634
Equity in Earnings of Unconsolidated Joint Venture	9,432	9,251
Corporate General and Administrative Expense	(21,254)	(8,003)
Legal Settlements		(1,800)
Other Non-Operating Income	200	571
Interest Expense, net	(8,846)	(6,632)
Earnings before Income Taxes	54,861	85,021
Income Taxes	(13,557)	(18,682)
Net Earnings	41,304	66,339
Net Actuarial Change in Benefit Plans, net of tax	33	56
Comprehensive Earnings	41,337	66,395
Eliminations [Member]
Equity in Earnings of Unconsolidated Joint Venture	(9,432)	(9,251)
Equity in Earnings of Subsidiaries	(55,742)	(67,258)
Earnings before Income Taxes	(65,174)	(76,509)
Net Earnings	(65,174)	(76,509)
Net Actuarial Change in Benefit Plans, net of tax	(33)	(56)
Comprehensive Earnings	(65,207)	(76,565)
Parent [Member] \| Reportable Legal Entities [Member]
Equity in Earnings of Unconsolidated Joint Venture	9,432	9,251
Equity in Earnings of Subsidiaries	55,742	67,258
Corporate General and Administrative Expense	(20,968)	(6,729)
Other Non-Operating Income	426	(93)
Interest Expense, net	(8,834)	(6,619)
Earnings before Income Taxes	35,798	63,068
Income Taxes	5,506	3,271
Net Earnings	41,304	66,339
Net Actuarial Change in Benefit Plans, net of tax	33	56
Comprehensive Earnings	41,337	66,395
Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Revenue	370,597	393,756
Cost of Goods Sold	295,268	302,122
Gross Profit	75,329	91,634
Equity in Earnings of Unconsolidated Joint Venture	9,432	9,251
Corporate General and Administrative Expense	(286)	(1,274)
Legal Settlements		(1,800)
Other Non-Operating Income	(226)	664
Interest Expense, net	(12)	(13)
Earnings before Income Taxes	84,237	98,462
Income Taxes	(19,063)	(21,953)
Net Earnings	65,174	76,509
Net Actuarial Change in Benefit Plans, net of tax	33	56
Comprehensive Earnings	$ 65,207	$ 76,565

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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