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Business Developments - Narrative (Details) $ in Thousands			3 Months Ended
Business Developments - Narrative (Details) $ in Thousands	Feb. 12, 2024 USD ($) loan	Jan. 24, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Business Acquisition [Line Items]
Goodwill			$ 2,868,068		$ 2,868,068	$ 2,631,465
Professional and outside services			$ 17,226	$ 12,981
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Mortgage Servicing Portfolio
Business Acquisition [Line Items]
Individual residential mortgage loans \| loan	9,184
Aggregate UPB	$ 1,400,000
Cash proceeds from sale of business	18,400
Mortgage servicing rights	6,700
Gain recognized on sale	$ 11,700
The Joint Venture
Business Acquisition [Line Items]
Joint venture ownership percentage			50.00%
Ametros
Business Acquisition [Line Items]
Goodwill		$ 228,185
Professional and outside services				$ 3,100
Ametros \| Core deposits
Business Acquisition [Line Items]
Recognized identifiable assets acquired		$ 182,800
Acquired intangible assets, useful life		25 years
Ametros \| Trade name
Business Acquisition [Line Items]
Recognized identifiable assets acquired		$ 6,100
Acquired intangible assets, useful life		5 years