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Acquisition - Purchase Price of PCD Loans (Details) - West Suburban Bancorp, Inc $ in Thousands	Dec. 01, 2021 USD ($)
Business Acquisition [Line Items]
Purchase price of PCD loans at acquisition	$ 1,502,118
PCI
Business Acquisition [Line Items]
Par value of acquired loans	108,241
Allowance for credit losses	(12,075)
Non-credit discount	(1,723)
Purchase price of PCD loans at acquisition	$ 94,443

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Par value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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