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Acquisition - Summary of Acquired Non-Impaired Loans as of Acquisition Date (Details) - Oak Park River Forest Bankshares, Inc. $ in Thousands | Apr. 30, 2019 USD ($)
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Business Acquisition [Line Items] |  |
Fair value | $ 204,496 |
Gross contractual amounts receivable | 254,755 |
Estimate of contractual cash flows not expected to be collected | 12,987 | [1]
Estimate of contractual cash flows expected to be collected | $ 241,768 |
[1] | Includes interest payments not expected to be collected due to loan prepayments as well as principal and interest payments not expected to be collected due to customer default.

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