Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Feb. 29, 2012	Feb. 28, 2011	Feb. 29, 2012	Feb. 28, 2011
Operating activities
Net earnings	$ 28,398	$ 28,334	$ 70,939	$ 69,470
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	14,653	15,789	40,626	47,259
Restructuring and other expense, non-cash				225
Provision for deferred income taxes	(667)	7,778	7,511	3,314
Bad debt expense	316	215	205	996
Equity in net income of unconsolidated affiliates, net of distributions	3,998	(2,997)	1,711	(6,813)
Net loss (gain) on sale of assets	143	(1,191)	(1,925)	(1,521)
Stock-based compensation	2,797	1,603	8,576	4,635
Changes in assets and liabilities:
Receivables	(28,643)	(24,591)	27,449	(39,713)
Inventories	(31,049)	(21,601)	23,726	4,729
Prepaid expenses and other current assets	9,576	(5,435)	13,126	(4,740)
Other assets	(1,046)	(2,020)	1,794	(1,212)
Accounts payable and accrued expenses	90,258	68,840	(56,871)	(25,302)
Other liabilities	(1,296)	354	86	4,012
Net cash provided by operating activities	87,438	65,078	136,953	55,339
Investing activities
Investment in property, plant and equipment, net	(5,769)	(5,101)	(15,800)	(15,911)
Acquisitions, net of cash acquired	(152,389)	(19,515)	(232,171)	(31,690)
Distributions from unconsolidated affiliates	44,023		43,238
Proceeds from sale of assets	3,178	183	14,525	6,690
Net cash used by investing activities	(110,957)	(24,433)	(190,208)	(40,911)
Financing activities
Net proceeds from (repayments of) short-term borrowings	15,329	(42,957)	108,460	80,778
Principal payments on long-term debt	(95)		(95)
Proceeds from issuance of common shares	1,186	1,077	9,709	2,415
Payments to noncontrolling interest	(3,168)	(2,496)	(9,744)	(9,072)
Repurchase of common shares			(52,120)	(75,092)
Dividends paid	(8,273)	(7,413)	(23,856)	(22,747)
Net cash provided by (used in) financing activities	4,979	(51,789)	32,354	(23,718)
Decrease in cash and cash equivalents	(18,540)	(11,144)	(20,901)	(9,290)
Cash and cash equivalents at beginning of period	53,806	60,870	56,167	59,016
Cash and cash equivalents at end of period	$ 35,266	$ 49,726	$ 35,266	$ 49,726

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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).