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	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 1,336	$ 1,042	$ 1,261	$ 990
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	75	60	150	112
Ending balance	1,411	1,102	1,411	1,102
Real estate loans \| Secured by one-to-four family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	742	661	816	584
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	61	29	(13)	106
Ending balance	803	690	803	690
Real estate loans \| Secured by multi-family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	79	45	80	38
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	(1)	2	(2)	9
Ending balance	78	47	78	47
Real estate loans \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	42	31	54	31
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	(9)	18	(21)	18
Ending balance	33	49	33	49
Real estate loans \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	205	107	148	84
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	6	(1)	63	22
Ending balance	211	106	211	106
Real estate loans \| Home equity lines of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	105	114	107	112
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	(2)	(5)	(4)	(3)
Ending balance	103	109	103	109
Other Loans Portfolio Segment \| Commercial & industrial loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	53	28	47	28
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	1	10	7	10
Ending balance	54	38	54	38
Other Loans Portfolio Segment \| Other/Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	110	56	9	113
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provisions	19	7	120	(50)
Ending balance	$ 129	$ 63	$ 129	$ 63

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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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- Definition

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

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