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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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