Segment Reporting - Segment Information (Details) - USD ($)
$ in Thousands
 3 Months Ended
Nov. 30, 2021
Nov. 30, 2020
Aug. 31, 2021
Segment Reporting Information [Line Items]      
Revenues $ 10,880,757 $ 8,715,643  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 10,880,757 8,715,643  
Operating earnings (loss) 314,974 7,443  
Interest Expense 23,432 25,050  
Other income 23,776 12,624  
Equity income from investments 151,345 50,023  
Income (loss) before income taxes 466,663 45,040  
Total assets 19,614,978   $ 17,576,275
Energy      
Segment Reporting Information [Line Items]      
Revenues, including intersegment revenues 2,468,343 1,357,845  
Revenues 2,303,987 1,257,847  
Intersegment Revenue (164,356) (99,998)  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 2,303,987 1,257,847  
Operating earnings (loss) 67,850 (68,385)  
Interest Income, Operating 488    
Interest Expense   (238)  
Other income 728 482  
Equity income from investments 1,100 489  
Income (loss) before income taxes 69,190 (67,176)  
Total assets 4,315,331    
Ag      
Segment Reporting Information [Line Items]      
Revenues, including intersegment revenues 8,577,403 7,450,305  
Revenues 8,569,259 7,445,402  
Intersegment Revenue (8,144) (4,903)  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 8,569,259 7,445,402  
Operating earnings (loss) 259,773 75,524  
Interest Expense 13,661 14,505  
Other income 20,579 11,817  
Equity income from investments 19,734 10,174  
Income (loss) before income taxes 286,425 83,010  
Total assets 9,335,801    
Nitrogen Production [Member]      
Segment Reporting Information [Line Items]      
Revenues, including intersegment revenues 0 0  
Intersegment Revenue 0 0  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 0 0  
Operating earnings (loss) (10,183) (7,623)  
Interest Expense 11,254 11,163  
Other income 1,547 1,566  
Equity income from investments 116,473 21,688  
Income (loss) before income taxes 96,583 4,468  
Total assets 2,796,671    
Corporate and Other      
Segment Reporting Information [Line Items]      
Revenues, including intersegment revenues 10,204 15,481  
Revenues 7,511 12,394  
Intersegment Revenue (2,693) (3,087)  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 7,511 12,394  
Operating earnings (loss) (2,466) 7,927  
Interest Expense 1,820 1,138  
Other income 1,073 277  
Equity income from investments 14,038 17,672  
Income (loss) before income taxes 14,465 24,738  
Total assets 3,167,175    
Other Segments      
Segment Reporting Information [Line Items]      
Revenues (175,193) (107,988)  
Intersegment Revenue 175,193 107,988  
Revenue From Contract With Customer Net of Intersegment Revenue Excluding Assessed Tax 0 0  
Operating earnings (loss) 0 0  
Interest Expense 151 (1,518)  
Other income 151 (1,518)  
Equity income from investments 0 0  
Income (loss) before income taxes 0 $ 0  
Total assets $ 0