Summary of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, $ in Thousands		12 Months Ended
Jul. 12, 2017 $ / shares shares	Dec. 31, 2019 USD ($) store	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Numbers of shares issued on mutual-to-stock conversion \| shares	1,653,125
Stock issued price per share on mutual-to-stock conversion \| $ / shares	$ 10.00
Number of branches \| store		3
Debt Securities, Trading \| $		$ 0	$ 0
Threshold Percentage of Value Decline in Equity Securities to be considered Other than Temporary Impairment		10.00%
Threshold Period of Value Decline in Equity Securities to be considered Other than Temporary Impairment		1 year
Purchase and maintain stock percent of total assets		0.04%
Percentage of outstanding FHLB advances		4.10%
Real Estate \| Residential \| Credit Concentration Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration Risk, Percentage		68.00%	69.00%

Represent federal home loan bank leverage capital required percent.

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Represent federal home loan bank leverage capital required percent of outstanding FHLB advances.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Represents the number of stores.

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Threshold percentage by which investments in equity securities have declined in value to be considered other than temporary impairment (OTTI).

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Threshold period for investment in equity securities in a continuous decline in value to be considered other than temporary impairment (OTTI), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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