Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Income Statement [Abstract]
Net sales	$ 759,109	$ 763,996	$ 2,193,110	$ 2,447,492
Cost of goods sold	595,011	648,451	1,780,180	2,094,045
Gross margin	164,098	115,545	412,930	353,447
Selling, general and administrative expense	86,895	80,928	251,220	260,294
Impairment of goodwill and long-lived assets	0	34,627	13,739	75,228
Restructuring and other expense, net	28,212	1,376	37,656	1,781
Incremental expenses related to Nikola gains	(781)	0	53,300	0
Operating income (loss)	49,772	(1,386)	57,015	16,144
Other income (expense):
Miscellaneous income, net	539	6,985	1,366	8,316
Interest expense	(7,558)	(7,362)	(22,696)	(24,157)
Equity in net income of unconsolidated affiliates	31,674	25,479	80,939	97,592
Gains on investment in Nikola	2,740	0	655,102	0
Loss on extinguishment of debt	0	0	0	(4,034)
Earnings before income taxes	77,167	23,716	771,726	93,861
Income tax expense	4,485	4,828	148,818	20,506
Net earnings	72,682	18,888	622,908	73,355
Net earnings attributable to noncontrolling interests	5,073	3,577	12,668	10,734
Net earnings attributable to controlling interest	$ 67,609	$ 15,311	$ 610,240	$ 62,621
Basic
Average common shares outstanding	52,149	54,930	53,076	55,078
Earnings per share attributable to controlling interest	$ 1.30	$ 0.28	$ 11.50	$ 1.14
Diluted
Average common shares outstanding	53,217	55,898	54,077	56,164
Earnings per share attributable to controlling interest	$ 1.27	$ 0.27	$ 11.28	$ 1.11
Common shares outstanding at end of period	51,813	54,598	51,813	54,598
Cash dividends declared per share	$ 0.25	$ 0.24	$ 0.75	$ 0.72