Segment Data - Sales and Operating Income (Loss) by Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
External sales:
Total sales	$ 638,970us-gaap_SalesRevenueNet	$ 755,242us-gaap_SalesRevenueNet	$ 2,009,543us-gaap_SalesRevenueNet	$ 2,064,986us-gaap_SalesRevenueNet
Operating income:
Total operating (loss) income	(120,392)us-gaap_OperatingIncomeLoss	76,830us-gaap_OperatingIncomeLoss	(393,143)us-gaap_OperatingIncomeLoss	185,376us-gaap_OperatingIncomeLoss
Interest expense	7,760us-gaap_InterestExpense	8,883us-gaap_InterestExpense	23,929us-gaap_InterestExpense	24,001us-gaap_InterestExpense
Other (income) expense, net	(378)us-gaap_OtherNonoperatingIncomeExpense	(561)us-gaap_OtherNonoperatingIncomeExpense	32us-gaap_OtherNonoperatingIncomeExpense	906us-gaap_OtherNonoperatingIncomeExpense
(Loss) income before income taxes	(127,774)	68,508	(417,104)	160,469
Industrial [Member]
External sales:
Total sales	354,810	399,669	1,104,225	1,108,546
Operating income:
Total operating (loss) income	35,311	51,403	121,123	124,441
Infrastructure [Member]
External sales:
Total sales	284,160	355,573	905,318	956,440
Operating income:
Total operating (loss) income	(153,100)	28,012	(505,799)	68,305
Corporate [Member]
Operating income:
Total operating (loss) income	$ (2,603)	$ (2,585)	$ (8,467)	$ (7,370)

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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