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Acquisition and Divestiture Activity (Details) - USD ($) $ in Millions		3 Months Ended
	Nov. 18, 2022	Mar. 31, 2023	Mar. 31, 2022
Business Acquisition [Line Items]
Deposits, health savings accounts	$ 382.0
Gain on sale of health savings accounts business	$ 90.7
First Midwest
Business Acquisition [Line Items]
Transaction costs, expensed		$ 14.6	$ 41.3

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- Definition

Business Combination, Acquisition Related Costs, Expensed

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- Definition

Deposits, Health Savings Accounts

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- Definition

Gain (Loss) on Sale of Health Savings Account Business

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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