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Acquisition (Details) - USD ($) $ in Thousands |  | 3 Months Ended |
--- | --- | --- | ---
Jan. 01, 2026 | Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Business Combination [Line Items] |  |  |  |
Goodwill |  | $ 253,805 |  | $ 146,539
FineMark Holdings, Inc. |  |  |  |
Business Combination [Line Items] |  |  |  |
Business Combination, Consideration Transferred, Equity Interest | $ 519,900 |  |  |
Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Fair Value | 4,614 | $ 4,614 | $ 0 |
Payments to Acquire Businesses, Gross | 8 |  |  |
Business Combination, Consideration Transferred | 524,487 |  |  |
Business Combinations, Recognized Asset Acquired, Loans, Net of Allowance for Credit Losses on Loans | 2,607,866 |  |  |
Business Combinations, Recognized Asset Acquired, Trading Securities | 541,967 |  |  |
Business Combinations, Recognized Asset Acquired, Other Investments | 27,180 |  |  |
Business Combinations, Recognized Asset Acquired, Interest Earning Deposits with Banks | 483,821 |  |  |
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent | 17,547 |  |  |
Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment | 47,074 |  |  |
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill | 138,082 |  |  |
Business Combinations, Recognized Asset Acquired, Other Assets | 102,979 |  |  |
Business Combination, Recognized Asset Acquired, Asset | 3,966,516 |  |  |
Business Combination, Recognized Liability Assumed, Non-Interest bearing deposits | 425,140 |  |  |
Business Combination, Recognized Liability Assumed, Interest bearing deposits | 2,684,381 |  |  |
Business Combination, Recognized Liability Assumed, Repurchase Agreements | 63,018 |  |  |
Business Combination, Recognized Liability Assumed, Other Borrowings | 351,458 |  |  |
Business Combination, Recognized Liability Assumed, Other Liabilities | 25,298 |  |  |
Business Combination, Recognized Liability Assumed, Liability | 3,549,295 |  |  |
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less) | 417,221 |  |  |
Goodwill | 107,266 |  |  |
FineMark Holdings, Inc. | Common Stock [Member] |  |  |  |
Business Combination [Line Items] |  |  |  |
Business Combination, Consideration Transferred, Equity Interest | $ 519,865 |  |  |

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