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v3.26.1

EQUITY-BASED COMPENSATION - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Mar. 31, 2026 | Mar. 31, 2025 | Sep. 30, 2025 | May 31, 2021 | Sep. 30, 2020 | May 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based payment arrangement, expense | $ 4,619 | $ 3,545 | $ 9,797 | $ 7,151 |  |  |  |
Income tax benefit (expense) related to equity-based compensation | $ 472 | (1,165) | $ 1,202 | (588) |  |  |  |
Weighted-average grant date fair value (in USD per share) |  |  | $ 12.41 |  |  |  |  |
Outstanding at end of period (in shares) | 8,850,572 |  | 8,850,572 |  | 7,881,236 |  |  |
Options exercisable at end of period (in shares) | 6,800,178 |  | 6,800,178 |  |  |  |  |
Unrecognized compensation expense related to unvested options at end of period | $ 19,895 |  | $ 19,895 |  |  |  |  |
Fair value of stock options that vested | $ 4,163 |  | $ 4,837 |  |  |  |  |
2018 Equity Incentive Award Plan |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Shares available for grant under the plan (in shares) | 2,303,073 |  | 2,303,073 |  |  |  |  | 3,500,000
Additional Class A common shares added at the beginning of calendar year as percentage of common stock outstanding at end of previous year (percent) |  |  |  |  |  |  |  | 4.00%
2020 Equity Incentive Award Plan |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Shares available for grant under the plan (in shares) | 2,021,344 |  | 2,021,344 |  |  | 3,000,000 | 1,500,000 |
Employee Stock Option |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based payment arrangement, expense | $ 1,855 | 1,502 | $ 3,201 | 3,825 |  |  |  |
Period for recognition of unrecognized compensation cost (in years) |  |  | 3 years 6 months |  |  |  |  |
Restricted stock units |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based payment arrangement, expense | $ 2,764 | 2,043 | $ 6,596 | 3,326 |  |  |  |
Period for recognition of unrecognized compensation cost (in years) |  |  | 2 years 7 months 6 days |  |  |  |  |
Granted (in USD per share) | $ 24.06 |  | $ 24.06 |  |  |  |  |
Cost not yet recognized, amount | $ 21,096 |  | $ 21,096 |  |  |  |  |
Vested in period, fair value | $ 5,449 |  | $ 9,693 |  |  |  |  |
Discontinued Operations, Held-for-Sale or Disposed of by Sale | Merchant Services Business |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Share-based payment arrangement, expense |  | $ 387 |  | $ 595 |  |  |  |

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