Loans - Schedule of Allowance for Loan Losses by Portfolio Segment and Class (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 1,206	$ 1,302
Provision for loan losses	0	0
Loans charged-off	(29)	(40)
Recoveries	2	188
Ending balance	1,179	1,450
Multi-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance			354
Ending balance	340		354
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance			277
Ending balance	288		277
Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance			96
Ending balance	92		96
Land [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance			6
Ending balance	6		6
First Mortgage Loans [Member] \| One To Four Family Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	392	589
Provision for loan losses	(22)	82
Ending balance	370	671
First Mortgage Loans [Member] \| Multi-Family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	354	252
Provision for loan losses	14	(6)
Loans charged-off	(28)
Ending balance	340	246
First Mortgage Loans [Member] \| Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	277	300
Provision for loan losses	11	(229)
Recoveries		186
Ending balance	288	257
First Mortgage Loans [Member] \| Construction Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	7
Provision for loan losses	6	(2)
Recoveries	1	2
Ending balance	14
First Mortgage Loans [Member] \| Land [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance		7	6
Provision for loan losses		6
Loans charged-off		(6)
Ending balance	6	7	6
Commercial, Consumer and Other Loans [Member] \| Other Automobile [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	66	56
Provision for loan losses	(3)	71
Loans charged-off	(1)	(16)
Ending balance	62	111
Commercial, Consumer and Other Loans [Member] \| Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses	(1)
Recoveries	1
Commercial, Consumer and Other Loans [Member] \| Home Equity Line of Credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	96	78
Provision for loan losses	(4)	77
Loans charged-off		(18)
Ending balance	92	137
Commercial, Consumer and Other Loans [Member] \| Commercial Business Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	8	20
Provision for loan losses	(1)	1
Ending balance	$ 7	$ 21

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

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

+ 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 (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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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 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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: 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=35738203&loc=SL6953423-111524

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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