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, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 855	$ 691	$ 811	$ 653
Charge Offs			(1)
Recoveries
Provisions	45	37	90	75
Ending Balance	900	728	900	728
Real estate loans: \| Secured by one-to-four family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	539	441	524	448
Charge Offs
Recoveries
Provisions	30	72	45	65
Ending Balance	569	513	569	513
Real estate loans: \| Secured by multi-family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	41	29	39	29
Charge Offs
Recoveries
Provisions	(2)	(1)		(1)
Ending Balance	39	28	39	28
Real estate loans: \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	8	5	6	6
Charge Offs
Recoveries
Provisions	10	2	12	1
Ending Balance	18	7	18	7
Real estate loans: \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	46	14	35	14
Charge Offs
Recoveries
Provisions	1	8	12	8
Ending Balance	47	22	47	22
Real estate loans: \| Home equity lines of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	104	97	101	87
Charge Offs
Recoveries
Provisions	1	1	4	11
Ending Balance	105	98	105	98
Other Loans Portfolio Segment \| Commercial & industrial loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	11	1	11	1
Charge Offs
Recoveries
Provisions	2	1	2	1
Ending Balance	13	2	13	2
Other Loans Portfolio Segment \| Other/Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	106	104	95	68
Charge Offs			(1)
Recoveries
Provisions	3	(46)	15	(10)
Ending Balance	$ 109	$ 58	$ 109	$ 58

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
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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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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- Definition

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

+ References

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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