Goodwill and Core Deposit Intangibles - Goodwill Narrative (Details) - USD ($) $ in Millions				12 Months Ended
	Jul. 01, 2023	Jul. 01, 2022	Feb. 01, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Impairment of goodwill	$ 0.0	$ 0.0
Reductions due to sale of health savings accounts				$ 15.7	$ 15.9	$ 9.9
Estimated useful lives of related deposits				12 years
Core Deposits Intangibles
Goodwill [Line Items]
Estimated useful lives of related deposits			10 years	10 years