v3.23.3

Borrowings (Tables) | 12 Months Ended
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Sep. 30, 2023
Debt Disclosure [Abstract] |
Components of Debt | The below table presents the components of the carrying value of the 2025 Notes, the 2027 Notes and the 2029 Notes as of September 30, 2023 and September 30, 2022:
|  | As of September 30, 2023 |  | As of September 30, 2022
($ in millions) |  | 2025 Notes |  | 2027 Notes |  | 2029 Notes |  | 2025 Notes |  | 2027 Notes
Principal |  | $ | 300.0 |  |  | $ | 350.0 |  |  | $ | 300.0 |  |  | $ | 300.0 |  |  | $ | 350.0 |
Unamortized financing costs |  | (1.1) |  |  | (2.5) |  |  | (3.5) |  |  | (1.8) |  |  | (3.2) |
Unaccreted discount |  | (0.7) |  |  | (0.6) |  |  | (3.4) |  |  | (1.2) |  |  | (0.7) |
Interest rate swap fair value adjustment |  | — |  |  | (40.5) |  |  | (7.0) |  |  | — |  |  | (42.0) |
Net carrying value |  | $ | 298.2 |  |  | $ | 306.4 |  |  | $ | 286.1 |  |  | $ | 297.0 |  |  | $ | 304.1 |
Fair Value |  | $ | 286.4 |  |  | $ | 301.8 |  |  | $ | 290.0 |  |  | $ | 283.1 |  |  | $ | 294.0 |
The below table presents the components of interest and other debt expenses related to the 2025 Notes, the 2027 Notes and the 2029 Notes for the year ended September 30, 2023:
($ in millions) | 2025 Notes |  | 2027 Notes |  | 2029 Notes
Coupon interest |  | $ | 10.5 |  |  | $ | 9.5 |  |  | $ | 2.7 |
Amortization of financing costs and discount |  | 1.3 |  |  | 0.9 |  |  | 0.2 |
Effect of interest rate swap |  | — |  |  | 13.4 |  |  | 0.6 |
Total interest expense |  | $ | 11.8 |  |  | $ | 23.8 |  |  | $ | 3.5 |
Coupon interest rate (net of effect of interest rate swaps) |  | 3.500 | % |  | 6.539 | % |  | 8.490 | %
The below table presents the components of interest and other debt expenses related to the 2025 Notes and the 2027 Notes for the year ended September 30, 2022:
($ in millions) | 2025 Notes |  | 2027 Notes
Coupon interest |  | $ | 10.5 |  |  | $ | 9.5 |
Amortization of financing costs and discount |  | 1.3 |  |  | 0.9 |
Effect of interest rate swap |  | — |  |  | (0.4) |
Total interest expense |  | $ | 11.8 |  |  | $ | 10.0 |
Coupon interest rate (net of effect of interest rate swap for 2027 Notes) |  | 3.500 | % |  | 2.585 | %
The below table presents the components of interest and other debt expenses related to the 2025 Notes and the 2027 Notes for the year ended September 30, 2021:
($ in millions) |  | 2025 Notes |  | 2027 Notes
Coupon interest |  | $ | 10.5 |  |  | $ | 3.5 |
Amortization of financing costs and discount |  | 1.3 |  |  | 0.3 |
Effect of interest rate swap |  | — |  |  | (1.1) |
Total interest expense |  | $ | 11.8 |  |  | $ | 2.7 |
Coupon interest rate (net of effect of interest rate swap for 2027 Notes) |  | 3.500 | % |  | 1.813 | %

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