Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017
Operating activities:
Net earnings	$ 37,792	$ 41,622	$ 94,750	$ 89,696
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	23,525	26,283	48,018	51,648
Impairment of goodwill and long-lived assets		8,289	2,381	8,289
Provision for (benefit from) deferred income taxes	3,289	(583)	22,223	7,351
Bad debt (income) expense	32	41	253	(21)
Equity in net income of unconsolidated affiliates, net of distributions	14,182	2,952	4,163	(4,803)
Net (gain) loss on assets	(312)	(10,680)	2,403	(9,255)
Stock-based compensation	3,456	3,787	6,612	7,194
Changes in assets and liabilities, net of impact of acquisitions:
Receivables	40,838	(46,097)	54,247	16,581
Inventories	5,866	9,871	(37,471)	(24,825)
Prepaid expenses and other current assets	(13,249)	3,622	(21,668)	4,765
Other assets	(1,194)	(626)	(1,260)	(976)
Accounts payable and accrued expenses	(71,711)	(21,577)	(100,496)	(48,368)
Other liabilities	2,190	2,478	994	5,461
Net cash provided by operating activities	44,704	19,382	75,149	102,737
Investing activities:
Investment in property, plant and equipment	(21,741)	(23,678)	(41,175)	(41,691)
Acquisitions, net of cash acquired		(523)		(285,028)
Distributions from unconsolidated affiliates	55,201		55,201
Proceeds from sale of assets	170	16,312	20,447	16,739
Net cash provided (used) by investing activities	33,630	(7,889)	34,473	(309,980)
Financing activities:
Net proceeds from short-term borrowings, net of issuance costs		302		600
Proceeds from long-term debt, net of issuance costs		(594)		197,685
Principal payments on long-term debt	(371)	(220)	(801)	(439)
Payments for issuance of common shares, net of tax withholdings	(658)	(722)	(4,749)	(3,996)
Payments to noncontrolling interests	(4,007)	(3,196)	(6,327)	(3,916)
Repurchase of common shares	(63,581)	(67,448)	(100,433)	(112,524)
Dividends paid	(13,533)	(13,256)	(26,252)	(26,034)
Net cash provided (used) by financing activities	(82,150)	(85,134)	(138,562)	51,376
Decrease in cash and cash equivalents	(3,816)	(73,641)	(28,940)	(155,867)
Cash and cash equivalents at beginning of period	96,843	195,855	121,967	278,081
Cash and cash equivalents at end of period	$ 93,027	$ 122,214	$ 93,027	$ 122,214