Annual report [Section 13 and 15(d), not S-K Item 405]

DEBT AND FINANCING ARRANGEMENTS - Narrative (Details)

v3.25.3
DEBT AND FINANCING ARRANGEMENTS - Narrative (Details)
 12 Months Ended
Mar. 11, 2025
shares
Sep. 30, 2025
USD ($)
shares
Sep. 30, 2024
USD ($)
Sep. 30, 2025
EUR (€)
shares
Sep. 30, 2024
EUR (€)
Line of Credit Facility [Line Items]          
Supplier finance program, obligation, current   $ 6,136,000 $ 3,014,000    
Supplier Finance Program, Obligation, Current, Statement of Financial Position [Extensible Enumeration]   Trade accounts payable Trade accounts payable Trade accounts payable Trade accounts payable
Other borrowings   $ 710,832,000 $ 776,467,000    
Class A common stock          
Line of Credit Facility [Line Items]          
Shares issued with shelf registration (in shares) | shares 1,250,000        
Class A common stock | ATM Program          
Line of Credit Facility [Line Items]          
Shares issued with shelf registration (in shares) | shares 3,000,000        
Shares remaining for sale | shares   1,250,000   1,250,000  
2027 Senior Secured Notes          
Line of Credit Facility [Line Items]          
Debt issuance costs   $ 3,890,000 5,249,000    
Other borrowings   $ 296,110,000 $ 294,751,000    
Other borrowings          
Line of Credit Facility [Line Items]          
Weighted-average interest rate on outstanding borrowings (as a percent)   2.40% 2.66% 2.40% 2.66%
Other borrowings   $ 7,151,000 $ 15,602,000    
Senior Notes 2027 | 2027 Senior Notes          
Line of Credit Facility [Line Items]          
Debt issued amount   $ 300,000,000      
Fixed interest rate (as a percent)   8.625%   8.625%  
Receivables Purchase Agreement          
Line of Credit Facility [Line Items]          
Facility limit   $ 75,000,000      
Receivables sold to purchasers   65,600,000 96,300,000    
Unsold receivables   63,720,000 58,183,000    
Principal amount of receivables sold   45,813,000 70,236,000    
Factored accounts receivable, outstanding     15,665,000    
Revolving credit facilities | March 2020 Debt Amendment          
Line of Credit Facility [Line Items]          
Maximum amount of borrowings available   750,000,000      
Maximum borrowing amount drawn In foreign currency   $ 350,000,000      
Rate spread adjustment (as a percent)   0.10%      
Interest rate during period (as a percent)   1.25%      
Unamortized costs   $ 3,918,000 4,961,000    
Revolving credit facilities | March 2020 Debt Amendment | Minimum          
Line of Credit Facility [Line Items]          
Variable interest rate (as a percent)   1.00%      
Line of credit facility, unused capacity, commitment fee percentage   0.15%      
Revolving credit facilities | March 2020 Debt Amendment | Maximum          
Line of Credit Facility [Line Items]          
Variable interest rate (as a percent)   2.00%      
Line of credit facility, unused capacity, commitment fee percentage   0.30%      
Domestic Revolving Credit Facility | March 2020 Debt Amendment          
Line of Credit Facility [Line Items]          
Maximum available for issuance of trade and standby letters of credit   $ 75,000,000      
Outstanding borrowings   $ 384,233,000 $ 410,527,000    
Weighted-average interest rate on outstanding borrowings (as a percent)   3.99% 4.59% 3.99% 4.59%
Foreign Line of Credit | Foreign Exchange Contract          
Line of Credit Facility [Line Items]          
Notional amount     $ 33,485,000 € 0 € 30,000,000.0
Foreign Line of Credit | Credit Facility With European Bank          
Line of Credit Facility [Line Items]          
Maximum amount of borrowings available   $ 7,043,000   6,000,000.0  
Outstanding borrowings   $ 774,000   € 659,000 € 0
Weighted-average interest rate on outstanding borrowings (as a percent)   4.16%   4.16%  
Foreign Line of Credit | Bank Guarantees | Credit Facility With European Bank          
Line of Credit Facility [Line Items]          
Maximum amount of borrowings available   $ 16,433,000   € 14,000,000.0