Allowance for Loan Losses and Foreclosed Real Estate - Allowance for loan losses allocated by loan class and the activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for loan losses:
Beginning Balance	$ 1,661	$ 1,411	$ 1,561	$ 1,261
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	75	75	175	225
Ending balance	1,736	1,486	1,736	1,486
Ending balance: related to loans individually evaluated for impairment	210	0	210	0
Ending balance: related to loans collectively evaluated for impairment	1,526	1,486	1,526	1,486
Loans receivables:
Ending balance	278,484	280,572	278,484	280,572
Ending balance: related to loans individually evaluated for impairment	989	0	989	0
Ending balance: related to loans collectively evaluated for impairment	277,495	280,572	277,495	280,572
Real estate loans
Loans receivables:
Ending balance	271,141		271,141
Real estate loans \| Secured by one-to-four family residences
Allowance for loan losses:
Beginning Balance	805	803	866	816
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	20	85	(41)	72
Ending balance	825	888	825	888
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	825	888	825	888
Loans receivables:
Ending balance	215,400	219,841	215,400	219,841
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	215,400	219,841	215,400	219,841
Real estate loans \| Secured by multi-family residences
Allowance for loan losses:
Beginning Balance	74	78	77	80
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	8	0	5	(2)
Ending balance	82	78	82	78
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	82	78	82	78
Loans receivables:
Ending balance	10,973	10,337	10,973	10,337
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	10,973	10,337	10,973	10,337
Real estate loans \| Construction
Allowance for loan losses:
Beginning Balance	20	33	24	54
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	9	(2)	5	(23)
Ending balance	29	31	29	31
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	29	31	29	31
Loans receivables:
Ending balance	5,706	6,277	5,706	6,277
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	5,706	6,277	5,706	6,277
Real estate loans \| Commercial real estate
Allowance for loan losses:
Beginning Balance	482	211	284	148
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	(2)	53	196	116
Ending balance	480	264	480	264
Ending balance: related to loans individually evaluated for impairment	180	0	180	0
Ending balance: related to loans collectively evaluated for impairment	300	264	300	264
Loans receivables:
Ending balance	21,961	21,650	21,961	21,650
Ending balance: related to loans individually evaluated for impairment	944	0	944	0
Ending balance: related to loans collectively evaluated for impairment	21,017	21,650	21,017	21,650
Real estate loans \| Home equity lines of credit
Allowance for loan losses:
Beginning Balance	105	103	103	107
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	(3)	1	(1)	(3)
Ending balance	102	104	102	104
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	102	104	102	104
Loans receivables:
Ending balance	17,101	17,012	17,101	17,012
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	17,101	17,012	17,101	17,012
Other Loan Portfolio Segment \| Commercial and industrial loans
Allowance for loan losses:
Beginning Balance	125	54	97	47
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	(1)	19	27	26
Ending balance	124	73	124	73
Ending balance: related to loans individually evaluated for impairment	30	0	30	0
Ending balance: related to loans collectively evaluated for impairment	94	73	94	73
Loans receivables:
Ending balance	7,296	5,399	7,296	5,399
Ending balance: related to loans individually evaluated for impairment	45	0	45	0
Ending balance: related to loans collectively evaluated for impairment	7,251	5,399	7,251	5,399
Other Loan Portfolio Segment \| Other loans
Allowance for loan losses:
Beginning Balance	50	129	110	9
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions (Credits)	44	(81)	(16)	39
Ending balance	94	48	94	48
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	94	48	94	48
Loans receivables:
Ending balance	47	56	47	56
Ending balance: related to loans individually evaluated for impairment	0	0	0	0
Ending balance: related to loans collectively evaluated for impairment	$ 47	$ 56	$ 47	$ 56

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- Definition

Amount before allowance of loans and leases and deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts held in portfolio.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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