Goodwill and Core Deposit Intangibles - Schedule of Future Estimated CDI Amortization Expense (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
2023	$ 13.6
2024	12.8
2025	10.1
2026	7.7
2027	6.4
Thereafter	16.2
Finite-Lived Intangible Assets, Net	66.8	$ 81.4
Core Deposits Intangibles
Finite-Lived Intangible Assets [Line Items]
2023	11.7
2024	10.9
2025	8.2
2026	5.8
2027	4.5
Thereafter	8.4
Finite-Lived Intangible Assets, Net	49.5	62.2
OCRI
Finite-Lived Intangible Assets [Line Items]
2023	1.9
2024	1.9
2025	1.9
2026	1.9
2027	1.9
Thereafter	7.8
Finite-Lived Intangible Assets, Net	$ 17.3	$ 19.2

Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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