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, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 900	$ 728	$ 811	$ 653
Charge Offs			(1)
Recoveries
Provisions	45	37	135	112
Ending Balance	945	765	945	765
Real estate loans: \| Secured by one-to-four family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	569	513	524	448
Charge Offs
Recoveries
Provisions	(15)	4	30	69
Ending Balance	554	517	554	517
Real estate loans: \| Secured by multi-family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	39	28	39	29
Charge Offs
Recoveries
Provisions		3		2
Ending Balance	39	31	39	31
Real estate loans: \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	18	7	6	6
Charge Offs
Recoveries
Provisions	9	1	21	2
Ending Balance	27	8	27	8
Real estate loans: \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	47	22	35	14
Charge Offs
Recoveries
Provisions	18		30	8
Ending Balance	65	22	65	22
Real estate loans: \| Home equity lines of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	105	98	101	87
Charge Offs
Recoveries
Provisions	3	2	7	13
Ending Balance	108	100	108	100
Other Loans Portfolio Segment \| Commercial & industrial loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	13	2	11	1
Charge Offs
Recoveries
Provisions	11	12	13	13
Ending Balance	24	14	24	14
Other Loans Portfolio Segment \| Other/Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	109	58	95	68
Charge Offs			(1)
Recoveries
Provisions	19	15	34	5
Ending Balance	$ 128	$ 73	$ 128	$ 73

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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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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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
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