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
Mar. 31, 2017	Mar. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 990	$ 811
Charge Offs		(1)
Recoveries
Provisions	52	45
Ending Balance	1,042	855
Real estate loans: \| Secured by one-to-four family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	584	524
Charge Offs
Recoveries
Provisions	77	15
Ending Balance	661	539
Real estate loans: \| Secured by multi-family residences
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	38	39
Charge Offs
Recoveries
Provisions	7	2
Ending Balance	45	41
Real estate loans: \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	31	6
Charge Offs
Recoveries
Provisions		2
Ending Balance	31	8
Real estate loans: \| Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	84	35
Charge Offs
Recoveries
Provisions	23	11
Ending Balance	107	46
Real estate loans: \| Home equity lines of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	112	101
Charge Offs
Recoveries
Provisions	2	3
Ending Balance	114	104
Other Loans Portfolio Segment \| Commercial & industrial loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	28	11
Charge Offs
Recoveries
Provisions
Ending Balance	28	11
Other Loans Portfolio Segment \| Other/Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	113	95
Charge Offs		(1)
Recoveries
Provisions	(57)	12
Ending Balance	$ 56	$ 106

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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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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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
-Paragraph 1
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