CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
Income Statement [Abstract]
Net sales	$ 5,829,002	$ 4,643,723	$ 3,844,069
Costs and expenses:
Cost of Goods and Services Sold	5,025,514	4,021,558	3,322,711
Selling, general and administrative expenses	463,271	401,452	387,354
Loss on debt extinguishment	0	0	22,672
Impairment of assets	384	14,372	1,730
Interest expense	71,373	40,957	44,151
Total costs and expenses	5,560,542	4,478,339	3,778,618
Earnings from continuing operations before income taxes	268,460	165,384	65,451
Income taxes	69,681	30,147	15,276
Earnings from continuing operations	198,779	135,237	50,175
Earnings (loss) from discontinued operations before income taxes	(528)	3,235	(9,840)
Income taxes (benefit)	158	(34)	(5,997)
Earnings (loss) from discontinued operations	(686)	3,269	(3,843)
Net earnings	$ 198,093	$ 138,506	$ 46,332
Basic earnings (loss) per share
Earnings from continuing operations	$ 1.69	$ 1.16	$ 0.43
Earnings (loss) from discontinued operations	(0.01)	0.03	(0.03)
Net earnings	1.68	1.19	0.40
Diluted earnings (loss) per share
Earnings from continuing operations	1.67	1.14	0.43
Earnings (loss) from discontinued operations	(0.01)	0.03	(0.03)
Net earnings	$ 1.66	$ 1.17	$ 0.39