v3.21.1

Loans - Summary of Information Regarding Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 40	$ 67
Recorded Investment	11,005	8,041
Unpaid Principal		68
Principal Balance		8,405
Reserve	369	67
Average Investment		59
Average Investment	9,704	3,582
Interest Recognized	774	128
Recorded Investment	11,005	7,974
Principal Balance	11,119	8,337
Average Investment	9,664	3,523
Interest Recognized	774	128
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal		5,840
Recorded Investment	6,277	5,840
Principal Balance	6,277
Average Investment	6,268	1,824
Interest Recognized	332	87
Commercial Land Development [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,492
Principal Balance	1,492
Average Investment	503	126
Interest Recognized	40
Commercial Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	2,804	1,091
Principal Balance	2,804	1,091
Average Investment	2,301	488
Interest Recognized	138	23
Residential real estate and consumer First mortgage [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment	36	62
Unpaid Principal		62
Reserve		62
Average Investment		43
Recorded Investment	411	1,016
Principal Balance	495	1,350
Average Investment	568	1,056
Interest Recognized	261	18
Residential real estate and consumer Home equity and lines of credit
Financing Receivable, Impaired [Line Items]
Recorded Investment	4	5
Unpaid Principal		6
Reserve		5
Average Investment		16
Recorded Investment	21	27
Principal Balance	51	56
Average Investment	24	$ 29
Interest Recognized	$ 3

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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1895 Bancorp of Wisconsin, Inc. 10-K