Consolidated Statements of Earnings (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Income Statement [Abstract]
Net sales	$ 855,859	$ 988,107
Cost of goods sold	738,568	845,110
Gross margin	117,291	142,997
Selling, general and administrative expense	90,823	90,641
Impairment of long-lived assets	40,601	2,381
Restructuring and other expense (income), net	455	(936)
Operating income (loss)	(14,588)	50,911
Other income (expense):
Miscellaneous income, net	695	265
Interest expense	(9,480)	(9,728)
Loss on extinguishment of debt	(4,034)	0
Equity in net income of unconsolidated affiliates	24,767	30,008
Earnings (loss) before income taxes	(2,640)	71,456
Income tax expense (benefit)	(185)	14,498
Net earnings (loss)	(2,455)	56,958
Net earnings attributable to noncontrolling interests	2,321	2,016
Net earnings (loss) attributable to controlling interest	$ (4,776)	$ 54,942
Basic
Average common shares outstanding	55,241	58,731
Earnings (loss) per share attributable to controlling interest	$ (0.09)	$ 0.94
Diluted
Average common shares outstanding	55,241	60,621
Earnings (loss) per share attributable to controlling interest	$ (0.09)	$ 0.91
Common shares outstanding at end of period	54,871	58,389
Cash dividends declared per share	$ 0.24	$ 0.23