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Federal Home Loan Bank Advances - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Total Borrowings	$ 24,806,000	$ 0
Total borrowings excluding for fair value related to acquisition	25,519,000
Total borrowings, fair value related to acquisition	700
Unsecured borrowings through correspondent banks	69,000,000	69,000,000
Unpledged securities which could be sold or used as collateral	116,300,000	73,700,000
Additional borrowings available from the Federal Home Loan Bank based on current pledging	1,600,000	9,000,000
Maximum unsecured borrowing available	97,000,000	119,000,000
Mortgage Loans at Cost [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Advances, secured by mortgage loans	$ 42,100,000	$ 14,900,000

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- Definition

Advances from Federal Home Loan Banks excluding fair value related to acquisition.

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Advances from Federal Home Loan Banks fair value related to acquisition.

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- Definition

Federal Home Loan Bank advances general debt obligations disclosures amount of available unused funds based on current pledging.

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Unpledged securities.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 470
-Section 45
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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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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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