Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Aug. 31, 2014	Aug. 31, 2013
Cash Flows From Operating Activities:
Net Income	$ 104,839	$ 106,889
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	15,048	14,431
Amortization	8,246	7,882
Deferred income taxes	1,984	(11,505)
Stock-based compensation expense	5,700	4,826
Other	(605)	(701)
Changes in assets and liabilities, net of effect from purchases and sales of businesses:
(Increase) in receivables	(72,292)	(76,455)
(Increase) in inventory	(17,338)	(23,439)
(Increase) in prepaid expenses and other current and long-term assets	(2,307)	(7,201)
(Decrease) in accounts payable	(115,686)	(83,264)
(Decrease) in accrued compensation and benefits	(70,880)	(46,001)
(Decrease) in accrued loss reserves	(8,311)	(499)
Increase in other accrued liabilities	29,911	47,701
(Decrease) in contingent payment		(61,894)
Other	(3,542)	(232)
Cash (Used For) Operating Activities	(125,233)	(129,462)
Cash Flows From Investing Activities:
Capital expenditures	(12,050)	(10,696)
Acquisition of businesses, net of cash acquired	(33,472)	(12,328)
Purchase of marketable securities	(5,034)	(20,152)
Proceeds from sales of marketable securities	7,512	17,786
Other	(319)	3,092
Cash (Used For) Investing Activities	(43,363)	(22,298)
Cash Flows From Financing Activities:
Additions to long-term and short-term debt	131,907	53,218
Reductions of long-term and short-term debt	(5,468)	(1,936)
Cash dividends	(31,987)	(29,836)
Repurchase of stock	(4,695)	(4,004)
Payments of acquisition-related contingent consideration	(24,750)
Other	244	(2,388)
Cash Provided By Financing Activities	65,251	15,054
Effect of Exchange Rate Changes on Cash and Cash Equivalents	(4,498)	(1,945)
Net Change in Cash and Cash Equivalents	(107,843)	(138,651)
Cash and Cash Equivalents at Beginning of Period	332,868	343,554
Cash and Cash Equivalents at End of Period	$ 225,025	$ 204,903