Schedule of Combined Financial Information for Unconsolidated Affiliates (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Feb. 28, 2014		Feb. 28, 2013	Feb. 28, 2014		Feb. 28, 2013	May 31, 2013
Investments in and Advances to Affiliates [Line Items]
Cash	$ 56,077			$ 56,077			$ 70,380
Receivable from partner	12,897	[1]		12,897	[1]		69,706	[1]
Other current assets	437,179			437,179			518,262
Noncurrent assets	296,033			296,033			350,681
Total assets	802,186			802,186			1,009,029
Current liabilities	136,419			136,419			181,111
Short-term borrowings	38,204			38,204			21,369
Current maturities of long-term debt	4,782			4,782			5,442
Long-term debt	269,461			269,461			274,750
Other noncurrent liabilities	18,105			18,105			18,345
Equity	335,215			335,215			508,012
Total liabilities and equity	802,186			802,186			1,009,029
Net sales	340,645		421,645	1,121,362		1,306,758
Gross margin	73,217		90,570	239,098		254,796
Operating income	48,752		61,387	164,824		169,997
Depreciation and amortization	8,622		9,979	28,063		29,089
Interest expense	2,494		2,212	6,950		6,681
Income tax expense	2,937		1,842	8,829		5,488
Net earnings	$ 44,018		$ 57,421	$ 149,801		$ 158,570

[1] Represents cash owed from a joint venture partner as a result of centralized cash management.