v3.25.2

Borrowings - Schedule of Components of Interest and Other Debt Expenses (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
2025 Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Coupon interest | $ 0.0 | $ 2.6 | $ 4.2 | $ 7.9
Amortization of financing costs and discount | 0.0 | 0.3 | 0.5 | 0.9
Effect of interest rate swap | 0.0 | 0.0 | 0.0 | 0.0
Total interest expense | $ 0.0 | $ 2.9 | $ 4.7 | $ 8.8
Coupon interest rate (net of effect of interest rate swaps) (as a percent) | 3.50% | 3.50% | 3.50% | 3.50%
2027 Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Coupon interest | $ 2.4 | $ 2.4 | $ 7.1 | $ 7.1
Amortization of financing costs and discount | 0.2 | 0.2 | 0.7 | 0.7
Effect of interest rate swap | 3.2 | 4.0 | 10.1 | 12.3
Total interest expense | $ 5.8 | $ 6.6 | $ 17.9 | $ 20.1
Coupon interest rate (net of effect of interest rate swaps) (as a percent) | 6.28% | 7.213% | 6.458% | 7.262%
2029 Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Coupon interest | $ 5.3 | $ 5.3 | $ 16.0 | $ 16.0
Amortization of financing costs and discount | 0.3 | 0.3 | 0.9 | 1.0
Effect of interest rate swap | 0.3 | 1.1 | 1.4 | 3.4
Total interest expense | $ 5.9 | $ 6.7 | $ 18.3 | $ 20.4
Coupon interest rate (net of effect of interest rate swaps) (as a percent) | 7.45% | 8.44% | 7.65% | 8.469%
2030 Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Coupon interest | $ 4.8 |  | $ 6.6 |
Amortization of financing costs and discount | 0.2 |  | 0.3 |
Effect of interest rate swap | 0.2 |  | 0.2 |
Total interest expense | $ 5.2 |  | $ 7.1 |
Coupon interest rate (net of effect of interest rate swaps) (as a percent) | 6.515% |  | 6.514% |

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