Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Aug. 31, 2018	Aug. 31, 2017
Income Statement [Abstract]
Net sales	$ 988,107	$ 848,237
Cost of goods sold	845,110	715,459
Gross margin	142,997	132,778
Selling, general and administrative expense	90,641	88,249
Impairment of long-lived assets	2,381
Restructuring and other expense (income), net	(936)	2,304
Operating income	50,911	42,225
Other income (expense):
Miscellaneous income, net	265	348
Interest expense	(9,728)	(8,807)
Equity in net income of unconsolidated affiliates	30,008	27,306
Earnings before income taxes	71,456	61,072
Income tax expense	14,498	12,998
Net earnings	56,958	48,074
Net earnings attributable to noncontrolling interests	2,016	2,540
Net earnings attributable to controlling interest	$ 54,942	$ 45,534
Basic
Average common shares outstanding	58,731	62,444
Earnings per share attributable to controlling interest	$ 0.94	$ 0.73
Diluted
Average common shares outstanding	60,621	64,590
Earnings per share attributable to controlling interest	$ 0.91	$ 0.70
Common shares outstanding at end of period	58,389	62,144
Cash dividends declared per share	$ 0.23	$ 0.21