Condensed Consolidating Statement of Earnings and Comprehensive Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018
Revenue	$ 393,756	$ 366,121
Cost of Goods Sold	302,122	280,062
Gross Profit	91,634	86,059
Equity in Earnings of Unconsolidated Joint Venture	9,251	9,876
Corporate General and Administrative Expense	(8,003)	(9,679)
Legal Settlements	(1,800)
Other Non-Operating Income	571	757
Interest Expense, net	(6,632)	(7,483)
Earnings before Income Taxes	85,021	79,530
Income Taxes	(18,682)	(24,648)
Net Earnings	66,339	54,882	$ 256,632
Net Actuarial Change in Benefit Plans, net of tax	56	197
Comprehensive Earnings	66,395	55,079
Eliminations [Member]
Equity in Earnings of Unconsolidated Joint Venture	(9,251)	(9,876)
Equity in Earnings of Subsidiaries	(67,258)	(58,296)
Earnings before Income Taxes	(76,509)	(68,172)
Net Earnings	(76,509)	(68,172)
Net Actuarial Change in Benefit Plans, net of tax	(56)	(197)
Comprehensive Earnings	(76,565)	(68,369)
Parent [Member]
Equity in Earnings of Unconsolidated Joint Venture	9,251	9,876
Equity in Earnings of Subsidiaries	67,258	58,296
Corporate General and Administrative Expense	(6,729)	(8,648)
Other Non-Operating Income	(93)	(167)
Interest Expense, net	(6,619)	(12,962)
Earnings before Income Taxes	63,068	46,395
Income Taxes	3,271	8,487
Net Earnings	66,339	54,882
Net Actuarial Change in Benefit Plans, net of tax	56	197
Comprehensive Earnings	66,395	55,079
Guarantor Subsidiaries [Member]
Revenue	393,756	366,121
Cost of Goods Sold	302,122	280,062
Gross Profit	91,634	86,059
Equity in Earnings of Unconsolidated Joint Venture	9,251	9,876
Corporate General and Administrative Expense	(1,274)	(1,031)
Legal Settlements	(1,800)
Other Non-Operating Income	664	924
Interest Expense, net	(13)	5,479
Earnings before Income Taxes	98,462	101,307
Income Taxes	(21,953)	(33,135)
Net Earnings	76,509	68,172
Net Actuarial Change in Benefit Plans, net of tax	56	197
Comprehensive Earnings	$ 76,565	$ 68,369

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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