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Acquisition (Pro Forma Information) (Details) - FineMark Holdings, Inc. - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Business Combination, Pro Forma Information [Line Items] |  |
Business Combination, Pro Forma Information, Pro Forma Revenue | $ 468,428 | $ 455,698
Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax | $ 150,695 | $ 135,690

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