Fair Value Accounting and Measurement - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial assets
Investment securities available for sale	$ 315,580	$ 262,967
Investment securities held to maturity		42,990
Accrued interest receivable	3,931	4,048
Mortgage servicing rights, net	1,500	1,500
Financial liabilities
Accrued interest payable	373	521
Carrying Amount
Financial assets
Cash and cash equivalents	48,739	26,323
Investment securities available for sale	315,580	262,967
Investment securities held to maturity		43,503
Loans held for sale	503
Loans receivable, net	878,437	863,852
FHLB stock	6,034	6,927
Accrued interest receivable	3,931	4,048
Mortgage servicing rights, net	871	1,044
Financial liabilities
Borrowings	112,930	136,552
Accrued interest payable	373	521
Carrying Amount \| Demand deposits
Financial liabilities
Deposits	693,565	678,908
Carrying Amount \| Time deposits
Financial liabilities
Deposits	308,080	261,352
Estimated Fair Value
Financial assets
Cash and cash equivalents	48,739	26,323
Investment securities available for sale	315,580	262,967
Investment securities held to maturity		42,990
Loans held for sale	503
Loans receivable, net	858,101	840,861
FHLB stock	6,034	6,927
Accrued interest receivable	3,931	4,048
Mortgage servicing rights, net	1,486	1,479
Financial liabilities
Borrowings	113,076	137,153
Accrued interest payable	373	521
Estimated Fair Value \| Demand deposits
Financial liabilities
Deposits	693,565	678,908
Estimated Fair Value \| Time deposits
Financial liabilities
Deposits	308,819	259,549
Estimated Fair Value \| Level 1
Financial assets
Cash and cash equivalents	48,739	26,323
Investment securities available for sale	0	0
Investment securities held to maturity		0
Loans held for sale	0
Loans receivable, net	0	0
FHLB stock	0	0
Accrued interest receivable	0	0
Mortgage servicing rights, net	0	0
Financial liabilities
Borrowings	0	0
Accrued interest payable	0	0
Estimated Fair Value \| Level 1 \| Demand deposits
Financial liabilities
Deposits	693,565	678,908
Estimated Fair Value \| Level 1 \| Time deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 2
Financial assets
Cash and cash equivalents	0	0
Investment securities available for sale	315,580	262,967
Investment securities held to maturity		42,990
Loans held for sale	503
Loans receivable, net	0	0
FHLB stock	6,034	6,927
Accrued interest receivable	3,931	4,048
Mortgage servicing rights, net	0	0
Financial liabilities
Borrowings	113,076	137,153
Accrued interest payable	373	521
Estimated Fair Value \| Level 2 \| Demand deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 2 \| Time deposits
Financial liabilities
Deposits	308,819	259,549
Estimated Fair Value \| Level 3
Financial assets
Cash and cash equivalents	0	0
Investment securities available for sale	0	0
Investment securities held to maturity		0
Loans held for sale	0
Loans receivable, net	858,101	840,861
FHLB stock	0	0
Accrued interest receivable	0	0
Mortgage servicing rights, net	1,486	1,479
Financial liabilities
Borrowings	0	0
Accrued interest payable	0	0
Estimated Fair Value \| Level 3 \| Demand deposits
Financial liabilities
Deposits	0	0
Estimated Fair Value \| Level 3 \| Time deposits
Financial liabilities
Deposits	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

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