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Acquisition - Summary of Fair Values of Assets and Liabilities Assumed as of Acquisition Date (Parenthetical) (Details) - Oak Park River Forest Bankshares, Inc. | Apr. 30, 2019 $ / shares shares
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Business Acquisition [Line Items] |
Stock issued (in shares) | shares | 1,464,558
Stock issued (in dollars per share) | $ / shares | $ 20.02

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- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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