Acquisitions - Schedule of Acquired Loans not Deemed to Have Credit Impairment (Details) - Inland Northwest Bank $ in Millions	Aug. 16, 2018 USD ($)
Business Acquisition [Line Items]
Contractually required principal and interest payments	$ 894.8
Contractual cash flows not expected to be collected	26.1
Fair value at acquisition	$ 693.2

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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