Loans - Summary of Aging of Recorded Investment in Past Due Loans (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	$ 0	$ 0
60 - 89 Days Past due	239
Greater than 90 Days Past Due Still on Accrual	0	0
Nonaccrual	1,232	1,295
Loans Not Past Due	57,698	60,355
Loans, recorded investment	59,169	61,650
Automobile [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	1,241	1,401
Loans, recorded investment	1,241	1,401
Land [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	208	213
Loans, recorded investment	208	213
One-To-Four-Family [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
60 - 89 Days Past due	178
Greater than 90 Days Past Due Still on Accrual	0	0
Nonaccrual	811	847
Loans Not Past Due	29,810	30,583
Loans, recorded investment	30,799	31,430
Multi-Family [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Nonaccrual	344	353
Loans Not Past Due	9,373	9,481
Loans, recorded investment	9,717	9,834
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	9,580	10,324
Loans, recorded investment	9,580	10,324
Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	416	260
Loans, recorded investment	416	260
Home Equity Line of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
60 - 89 Days Past due	61
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	6,450	7,360
Loans, recorded investment	6,511	7,360
Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Nonaccrual	77	95
Loans Not Past Due	619	731
Loans, recorded investment	696	826
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 Days Past due	0	0
Greater than 90 Days Past Due Still on Accrual	0	0
Loans Not Past Due	1	2
Loans, recorded investment	$ 1	$ 2

Financing Receivable Recorded Investment Not Past Due

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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