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Note 7 - Property, Equipment and Software (Tables) | 12 Months Ended
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Dec. 31, 2024
Notes Tables |
Schedule of Depreciation Expense [Table Text Block] |
​ |  | Year ended December 31, |
​ |  | 2024 |  |  | 2023 |  |  | 2022 |
Depreciation expense |  | $ | 17.4 |  |  | $ | 18.4 |  |  | $ | 21.6 |
​
Property, Plant and Equipment [Table Text Block] |
​ | ​ | Depreciation |  | December 31, |
​ |  | period |  | 2024 |  |  | 2023 |
Furniture, fixtures and computer equipment |  | 3 - 5 years |  | $ | 53.0 |  |  | $ | 50.1 |
Leasehold improvements |  | Over the shorter of the useful life or the lease term |  |  | 53.7 |  |  |  | 47.7 |
Computer software | ​ | 3 years |  |  | 95.2 |  |  |  | 103.3 |
Property, equipment and software, gross | ​ | ​ |  | $ | 201.9 |  |  | $ | 201.1 |
Accumulated depreciation | ​ | ​ |  |  | (162.5 | ) |  |  | (156.9 | )
Property, equipment and software, net | ​ | ​ |  | $ | 39.4 |  |  | $ | 44.2 |

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- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 360 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 + Details
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