Segment Reporting - Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	$ 38,448,033	$ 28,406,365	$ 31,900,453
Intersegment Revenue	0	0	0
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	38,448,033	28,406,365	31,900,453
Operating earnings (loss)	205,797	277,265	659,602
Interest expense	104,565	116,977	167,065
Other income	(59,559)	(39,875)	(86,309)
Equity income from investments	(354,529)	(186,715)	(236,755)
Income before income taxes	515,320	386,878	815,601
Capital expenditures	317,794	418,359	443,216
Depreciation and amortization, including amortization of deferred major maintenance	461,730	477,375	473,211
Total assets	17,576,275	15,993,947
Nitrogen Production
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	0	0	0
Intersegment Revenue	0	0	0
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	0	0	0
Operating earnings (loss)	(35,432)	(33,497)	(35,046)
Interest expense	44,461	45,255	55,226
Other income	(2,489)	(2,635)	(2,769)
Equity income from investments	(198,439)	(127,954)	(160,373)
Income before income taxes	121,035	51,837	72,870
Capital expenditures	0	0	0
Depreciation and amortization, including amortization of deferred major maintenance	0	0	0
Total assets	2,683,652	2,681,616
Ag
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	32,058,064	22,940,712	24,736,425
Intersegment Revenue	(22,722)	(14,613)	(16,353)
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	32,035,342	22,926,099	24,720,072
Operating earnings (loss)	265,362	82,543	65,181
Interest expense	65,099	71,682	101,386
Other income	(47,452)	(35,560)	(74,774)
Equity income from investments	(50,381)	(7,303)	(4,447)
Income before income taxes	298,096	53,724	43,016
Capital expenditures	148,770	158,903	110,197
Depreciation and amortization, including amortization of deferred major maintenance	182,210	196,510	208,294
Total assets	7,451,559	6,325,857
Energy
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	6,812,478	5,820,154	7,581,450
Intersegment Revenue	(437,217)	(389,020)	(462,374)
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	6,375,261	5,431,134	7,119,076
Operating earnings (loss)	(15,775)	219,861	615,662
Interest expense	1,113	308	5,719
Other income	(2,819)	(3,005)	(5,548)
Equity income from investments	(3,473)	(2,759)	(2,697)
Income before income taxes	(10,596)	225,317	618,188
Capital expenditures	112,160	175,169	268,877
Depreciation and amortization, including amortization of deferred major maintenance	245,273	245,983	233,624
Total assets	4,286,677	4,447,526
Foods
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	0	0	0
Intersegment Revenue	0	0	0
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	0	0	0
Operating earnings (loss)	(10,617)	(9,847)	(8,912)
Interest expense	0	0	0
Other income	0	0	0
Equity income from investments	(78,519)	(34,026)	(51,608)
Income before income taxes	67,902	24,179	42,696
Capital expenditures	0
Depreciation and amortization, including amortization of deferred major maintenance	0	0	0
Total assets	388,612	381,351
Corporate and Other
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	46,476	55,567	68,710
Intersegment Revenue	(9,046)	(6,435)	(7,405)
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	37,430	49,132	61,305
Operating earnings (loss)	2,259	18,205	22,717
Interest expense	1,804	11,806	11,684
Other income	(14,711)	(10,749)	(10,168)
Equity income from investments	(23,717)	(14,673)	(17,630)
Income before income taxes	38,883	31,821	38,831
Capital expenditures	56,864	84,287	64,142
Depreciation and amortization, including amortization of deferred major maintenance	34,247	34,882	31,293
Total assets	2,765,775	2,157,597
Other Segments
Segment Reporting Information [Line Items]
Revenue From Contract With Customer, Including Intersegment Revenue, Excluding Assessed Tax	(468,985)	(410,068)	(486,132)
Intersegment Revenue	468,985	410,068	486,132
RevenueFromContractWithCustomerNetofIntersegmentRevenueExcludingAssessedTax	0	0	0
Operating earnings (loss)		0	0
Interest expense	(7,912)	(12,074)	(6,950)
Other income	7,912	12,074	6,950
Equity income from investments		0	0
Income before income taxes	0	0	0
Capital expenditures	0	0	0
Depreciation and amortization, including amortization of deferred major maintenance	0	0	$ 0
Total assets	$ 0	$ 0