Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015
Operating activities:
Net earnings	$ 49,867	$ 25,751	$ 118,403	$ 60,746
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	21,645	20,547	43,476	41,987
Impairment of long-lived assets		22,962	0	25,962
Provision for (benefit from) deferred income taxes	2,316	(9,851)	2,336	(15,391)
Bad debt (income) expense	232	(2)	151	8
Equity in net income of unconsolidated affiliates, net of distributions	(2,824)	(10,389)	1,074	(15,902)
Net (gain) loss on sale of assets	(2,912)	(5,854)	1,484	(4,248)
Stock-based compensation	3,824	3,880	6,960	7,657
Changes in assets and liabilities, net of impact of acquisitions :
Receivables	(7,156)	23,474	9,798	66,103
Inventories	31,875	31,645	(18,523)	23,821
Prepaid expenses and other current assets	(1,737)	17,467	5,425	28,633
Other assets	1,165	(3,245)	2,411	(2,803)
Accounts payable and accrued expenses	(65,946)	(72,846)	(22,885)	(31,220)
Other liabilities	950	7,487	2,094	4,300
Net cash provided by operating activities	31,299	51,026	152,204	189,653
Investing activities:
Investment in property, plant and equipment	(14,730)	(21,995)	(31,046)	(60,492)
Acquisitions, net of cash acquired		(2,950)		(2,950)
Investments in unconsolidated affiliates		(226)		(1,913)
Proceeds from sale of assets	799	9,325	956	9,456
Net cash used by investing activities	(13,931)	(15,846)	(30,090)	(55,899)
Financing activities:
Net proceeds from (repayments of) short-term borrowings	(1,037)	27,499	(2,154)	(41,012)
Proceeds from long-term debt				921
Principal payments on long-term debt	(218)	(220)	(437)	(428)
Proceeds from issuance of common shares, net of tax withholdings	(2,849)	3,666	2,972	3,064
Payments to noncontrolling interests	(6,781)	(1,564)	(6,781)	(4,900)
Repurchase of common shares		(43,914)		(71,496)
Dividends paid	(12,828)	(12,065)	(24,722)	(23,616)
Net cash used by financing activities	(23,713)	(26,598)	(31,122)	(137,467)
Increase (decrease) in cash and cash equivalents	(6,345)	8,582	90,992	(3,713)
Cash and cash equivalents at beginning of period	181,525	18,772	84,188	31,067
Cash and cash equivalents at end of period	$ 175,180	$ 27,354	$ 175,180	$ 27,354