Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2011	Nov. 30, 2010
Operating activities
Net earnings	$ 14,201	$ 16,883	$ 42,541	$ 41,136
Adjustments to reconcile net earnings to net cash provided (used) by operating activities:
Depreciation and amortization	13,119	15,646	25,973	31,470
Restructuring and other expense (income), non-cash		(32)		225
Provision for deferred income taxes	500	(1,365)	8,178	(4,464)
Bad debt expense (income)	(140)	776	(111)	781
Equity in net income of unconsolidated affiliates, net of distributions	2,782	(2,160)	(2,287)	(3,816)
Net loss (gain) on sale of assets	(1,653)	354	(2,068)	(329)
Stock-based compensation	2,578	1,579	5,779	3,033
Changes in assets and liabilities:
Receivables	28,717	8,100	56,092	(15,122)
Inventories	48,860	31,799	54,775	26,330
Prepaid expenses and other current assets	2,940	1,437	3,550	695
Other assets	1,567	107	2,840	807
Accounts payable and accrued expenses	(50,281)	(15,158)	(147,129)	(94,143)
Other liabilities	1,165	1,491	1,382	3,658
Net cash provided (used) by operating activities	64,355	59,457	49,515	(9,739)
Investing activities
Investment in property, plant and equipment, net	(3,559)	(4,477)	(10,031)	(10,810)
Acquisitions, net of cash acquired	(38,782)		(79,782)	(12,175)
Investments in unconsolidated affiliates			(785)
Proceeds from sale of assets	6,306	4,366	11,347	6,508
Net cash used by investing activities	(36,035)	(111)	(79,251)	(16,477)
Financing activities
Net proceeds from (repayments of) short-term borrowings	16,881	(41,375)	93,131	123,735
Proceeds from issuance of common shares	315	1,036	8,523	1,338
Payments to noncontrolling interest	(3,456)	(3,457)	(6,576)	(6,577)
Repurchase of common shares	(16,715)	(12,137)	(52,120)	(75,092)
Dividends paid	(8,414)	(7,408)	(15,583)	(15,334)
Net cash provided (used) by financing activities	(11,389)	(63,341)	27,375	28,070
Increase (decrease) in cash and cash equivalents	16,931	(3,995)	(2,361)	1,854
Cash and cash equivalents at beginning of period	36,875	64,865	56,167	59,016
Cash and cash equivalents at end of period	$ 53,806	$ 60,870	$ 53,806	$ 60,870

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).