Goodwill and Core Deposit Intangibles - Goodwill Carrying Value (Details) $ in Millions	Jun. 30, 2025 USD ($)
Goodwill [Roll Forward]
Net carrying value at beginning of the period	$ 1,100.9
Net carrying value at end of period	$ 1,100.9

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details