v3.26.3
LONG-TERM DEBT - Narrative (Details)
3 Months Ended 9 Months Ended
Nov. 03, 2026
USD ($)
May 29, 2026
USD ($)
May 21, 2026
USD ($)
Nov. 13, 2024
USD ($)
Nov. 15, 2023
USD ($)
Sep. 20, 2023
USD ($)
shares
Sep. 30, 2026
USD ($)
Sep. 30, 2025
USD ($)
Sep. 30, 2026
USD ($)
aircraft
Sep. 30, 2025
USD ($)
Nov. 04, 2026
USD ($)
May 30, 2026
USD ($)
Dec. 31, 2023
USD ($)
Debt Instrument [Line Items]                          
Amortization of deferred financing costs and debt discount                 $ 37,121,000 $ 10,698,000      
Proceeds from long-term debt                 401,849,000 33,906,000      
Long-term debt             $ 1,009,642,000   1,009,642,000        
Term Loans                          
Debt Instrument [Line Items]                          
Long-term debt fair value                         $ 44,900,000
Fair value allocation                         9,400,000
Initial Issuance                          
Debt Instrument [Line Items]                          
Allocation on relative fair value basis                         64,200,000
Issuance costs           $ 25,400,000              
Deferred Issuance                          
Debt Instrument [Line Items]                          
Common stock issued (in shares) | shares           26,496,261              
Allocation on relative fair value basis                         240,900,000
Private Placement, Reallocated Shares                          
Debt Instrument [Line Items]                          
Deferred issuance costs                         $ 30,600,000
Term Loan                          
Debt Instrument [Line Items]                          
Issuance costs           $ 4,100,000              
Common Stock | Initial Issuance                          
Debt Instrument [Line Items]                          
Common stock issued (in shares) | shares           7,065,683              
Series A Equipment Notes | Notes Payable                          
Debt Instrument [Line Items]                          
Aggregate original principal amount       $ 332,000,000.0                  
Aggregate principal amount       $ 331,300,000                  
Debt instrument gross proceeds (in percent)       98.75%                  
Series A Equipment Notes | Notes Payable | Subsequent Event                          
Debt Instrument [Line Items]                          
Aggregate original principal amount $ 332,000,000.0                        
Proceeds from long-term debt $ 17,400,000                        
Series A Equipment Notes | Notes Payable | Asset Pledged as Collateral                          
Debt Instrument [Line Items]                          
Flight equipment             279,700,000   $ 279,700,000        
Series A Equipment Notes | Notes Payable | Aircraft                          
Debt Instrument [Line Items]                          
Number of aircraft | aircraft                 44        
Series A Equipment Notes | Notes Payable | Closing Date to the end of the Availability Period                          
Debt Instrument [Line Items]                          
Debt instrument spread on variable rate (in percent)       1.75%                  
Series A Equipment Notes | Notes Payable | Immediately after Availability Period to November 13, 2028                          
Debt Instrument [Line Items]                          
Debt instrument spread on variable rate (in percent)       2.25%                  
Series A Equipment Notes | Notes Payable | November 13, 2028 to Maturity                          
Debt Instrument [Line Items]                          
Debt instrument spread on variable rate (in percent)       2.75%                  
Series A Equipment Notes | Notes Payable | Period One                          
Debt Instrument [Line Items]                          
Annual amortization of principal percent (in percent)       10.00%                  
Series A Equipment Notes | Notes Payable | Period Two                          
Debt Instrument [Line Items]                          
Annual amortization of principal percent (in percent)       12.00%                  
Series B Equipment Notes | Notes Payable                          
Debt Instrument [Line Items]                          
Aggregate original principal amount     $ 68,000,000.0                    
Aggregate principal amount     $ 68,000,000.0           $ 68,000,000.0        
Debt instrument gross proceeds (in percent)     100.00%                    
Stated rate (in percent)     5.97%                    
Series B Equipment Notes | Notes Payable | Asset Pledged as Collateral                          
Debt Instrument [Line Items]                          
Flight equipment             247,900,000   $ 247,900,000        
Series B Equipment Notes | Notes Payable | Aircraft                          
Debt Instrument [Line Items]                          
Number of aircraft | aircraft                 40        
Revolving Equipment Notes | Notes Payable                          
Debt Instrument [Line Items]                          
Amortization of deferred financing costs and debt discount             200,000 $ 200,000 $ 700,000 1,100,000      
Credit Agreement                          
Debt Instrument [Line Items]                          
Issuance costs           $ 29,500,000              
Credit Agreement | Term Loan and Revolving Credit Facility | 2023 Revolving Credit Facility                          
Debt Instrument [Line Items]                          
Aggregate original principal amount         $ 100,000,000.0 $ 100,000,000.0              
Aggregate principal amount             45,000,000.0   145,000,000.0        
Stated rate (in percent)           10.00%              
Unrestricted cash required         100,000,000.0                
Repayments of lines of credit             0   64,700,000        
Long-term line of credit             82,600,000   82,600,000        
Remaining borrowing capacity             17,400,000   17,400,000        
Commitment fee (in percent)           2.00%              
Credit Agreement | Term Loan and Revolving Credit Facility | 2023 Revolving Credit Facility | Subsequent Event                          
Debt Instrument [Line Items]                          
Aggregate original principal amount                     $ 100,000,000.0    
Stated rate (in percent)                     10.00%    
Unrestricted cash required                     $ 100,000,000.0    
Additional borrowing available                     $ 100,000,000.0    
Credit Agreement | Term Loan and Revolving Credit Facility | 2023 Revolving Credit Facility | Indirect Guarantee of Indebtedness                          
Debt Instrument [Line Items]                          
Aggregate original principal amount             100,000,000.0   100,000,000.0        
Credit Agreement | Term Loan and Revolving Credit Facility | Term Loans                          
Debt Instrument [Line Items]                          
Stated rate (in percent)   12.00%                      
Amortization of deferred financing costs and debt discount             14,800,000 $ 4,800,000 35,300,000 $ 9,600,000      
Issuances         390,000,000.0 $ 350,000,000.0 390,000,000.0   390,000,000.0        
Proceeds from long-term debt         39,200,000 $ 343,000,000.0              
Increment principal amount         40,000,000.0                
Credit agreement interest rate (in percent)           2.00%              
Long-term debt         8,700,000 $ 41,400,000              
Unamortized debt issuance costs         700,000 3,400,000              
Unamortized debt discount         $ 30,600,000 $ 305,200,000              
Term loan maturity   91 days                      
Default rate increase   2.00%                      
Default alternate base rate increase   2.00%                      
2024 Revolving Equipment Notes Facility | Term Loan and Revolving Credit Facility | 2023 Revolving Credit Facility | Indirect Guarantee of Indebtedness                          
Debt Instrument [Line Items]                          
Aggregate original principal amount             400,000,000.0   400,000,000.0        
2026 Term Loan | Term Loan and Revolving Credit Facility | Term Loans                          
Debt Instrument [Line Items]                          
Aggregate original principal amount   $ 100,000,000.0                      
Amortization of deferred financing costs and debt discount             $ 1,000,000.0   $ 600,000        
Additional borrowing available                       $ 100,000,000.0  
2023 Term Loans | Term Loan and Revolving Credit Facility | Term Loans                          
Debt Instrument [Line Items]                          
Stated rate (in percent)           10.00%