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Subsequent Events (Details) - Subsequent Event - Banco Santander - USD ($) $ / shares in Units, $ in Billions |  | 6 Months Ended
--- | --- | ---
Feb. 02, 2026 | Dec. 31, 2026
Transaction Agreement, Webster Virginia Corporation And Webster Financial Corporation |  |
Subsequent Event [Line Items] |  |
Aggregate transaction value expected | $ 12.3 |
Transaction Agreement, Webster Financial Corporation | Forecast |  |
Subsequent Event [Line Items] |  |
Price per share (in dollars per share) |  | $ 48.75
American depository receipts transferred (in shares) |  | 2.0548

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