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Composition of Certain Financial Statement Captions - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Items Included in Consolidated Statement of Financial Condition [Abstract] |  |  |  |  |
Depreciation | $ 7,485,000 | $ 8,341,000 | $ 23,077,000 | $ 25,097,000 |
Deferred contract costs | 49,113,000 |  | 49,113,000 |  | $ 45,855,000
Capitalized contract cost, amount capitalized during period | $ 5,333,000 | $ 5,326,000 | 13,528,000 | 10,237,000 |
Amortization of deferred contract costs |  |  | 9,875,000 | $ 7,931,000 |
Capitalized contract cost impairment |  |  | $ 0 |  |

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