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CREDIT AGREEMENT - Additional Information (Detail)
3 Months Ended
Jan. 31, 2018
USD ($)
Feb. 20, 2018
USD ($)
Nov. 22, 2017
USD ($)
Apr. 30, 2017
USD ($)
Apr. 28, 2017
USD ($)
aircraft
Line of credit          
Debt Instrument [Line Items]          
Increase in debt to total capitalization ratio (as percent) 5.00%        
Line of credit | 2018          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         $ 105,000,000
Revolving credit facility, capital expenditure limitation with the permitted carry over         125,000,000
Line of credit | 2019          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         110,000,000
Line of credit | 2020          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         115,000,000
Line of credit | 2021          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         120,000,000
Line of credit | 2022          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         125,000,000
Line of credit | 2017          
Debt Instrument [Line Items]          
Revolving credit facility, permitted carry over of capital expenditure limitation         20,000,000
Line of credit | Revolving Credit Facility          
Debt Instrument [Line Items]          
Revolving credit facility, maximum borrowing capacity         $ 900,000,000.0
Revolving credit facility, maximum debt to total capitalization ratio (as percent)         0.5
Revolving credit facility, minimum net worth requirement       $ 1,007,200,000  
Revolving credit facility, outstanding borrowings $ 0        
Revolving credit facility, remaining available balance 876,500,000        
Line of credit | Revolving Credit Facility | Subsequent Event          
Debt Instrument [Line Items]          
Revolving credit facility, outstanding borrowings   $ 0      
Revolving credit facility, remaining available balance   876,500,000      
Line of credit | Letter of Credit          
Debt Instrument [Line Items]          
Revolving credit facility, outstanding borrowings $ 23,500,000        
Line of credit | Letter of Credit | Subsequent Event          
Debt Instrument [Line Items]          
Revolving credit facility, outstanding borrowings   $ 23,500,000      
Construction expenditure limitation | Revolving Credit Facility          
Debt Instrument [Line Items]          
Revolving credit facility, construction expenditure limitation     $ 135,000,000   $ 0
Construction expenditure limitation | Revolving Credit Facility | Unknown City and State          
Debt Instrument [Line Items]          
Revolving credit facility, construction expenditure limitation         210,000,000
Construction expenditure limitation | Revolving Credit Facility | Floowood, Mississippi          
Debt Instrument [Line Items]          
Revolving credit facility, construction expenditure limitation         15,000,000
Processing complex | Revolving Credit Facility | Unknown City and State          
Debt Instrument [Line Items]          
Revolving credit facility, construction expenditure limitation         60,000,000
Aircraft expenditure | Revolving Credit Facility          
Debt Instrument [Line Items]          
Revolving credit facility, capital expenditure limitation         $ 70,000,000
Number of aircraft purchased | aircraft         3