Investments in Unconsolidated Affiliates - Schedule of Combined Financial Information for Unconsolidated Affiliates (Detail) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	May 31, 2020
Investments in and Advances to Affiliates [Line Items]
Cash	$ 45,319		$ 68,730
Other current assets	541,267		528,631
Total assets	3,131,053		2,331,515
Current liabilities	542,184		388,238
Short-term borrowings			500
Current maturities of long-term debt	19,097		37,542
Long-term debt	327,246		346,690
Other noncurrent liabilities	71,333		73,656
Shareholders' equity - controlling interest	1,382,785		820,821
Total liabilities and equity	3,131,053		2,331,515
Net sales	702,909	$ 855,859
Gross margin	113,358	117,291
Operating income	57,953	66,223
Depreciation and amortization	7,730	7,089
Interest expense	2,945	3,367
Income tax expense	1,730	581
Net earnings from discontinued operations		2,812
Net earnings (loss)	618,738	(2,455)
Equity Method Investment, Nonconsolidated Investee, Other [Member]
Investments in and Advances to Affiliates [Line Items]
Noncurrent assets	396,757		399,731
Total assets	983,343		997,092
Current liabilities	185,271		174,709
Shareholders' equity - controlling interest	380,396		363,995
Total liabilities and equity	983,343		$ 997,092
Net sales	405,320	470,205
Gross margin	93,049	97,536
Net earnings from continuing operations	56,573	61,141
Net earnings (loss)	$ 56,573	$ 63,953