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Proposed Merger with West Suburban Bancorp, Inc (Details) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Jul. 25, 2021 USD ($) shares
Business Acquisition [Line Items] |  |
Expected percentage of shares to be held by the stockholders | 64.00% |
West Suburban Bancorp, Inc |  |
Business Acquisition [Line Items] |  |
Shares issued or issuable | shares |  | 42.413
Cash consideration for each share | $ |  | $ 271.15
Exchange ratio | 42.413 |
Expected percentage of shares to be held by the stockholders | 36.00% |

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