Goodwill and Core Deposit Intangibles - Goodwill Narrative (Details) - USD ($) $ in Millions				12 Months Ended
Jul. 01, 2020	Jul. 01, 2019	Jul. 01, 2018	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Line Items]
Finite-Lived Intangible Asset, Useful Life				10 years
Goodwill				$ 621.6	$ 621.6
Impairment of goodwill	$ 0.0	$ 0.0	$ 0.0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration