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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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The amount of cash consideration for each share of common stock of held by the acquiree.

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Number of shares issued for each share under the merger agreement.

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The expected percentage of shares to be held by the stockholders after the completion of business combination.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187143-122770

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