Loans - Summary of Loans Individually Evaluated for Impairment by Class (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance	$ 2,268	$ 4,543	$ 2,161
Loans, With no related allowance recorded, Recorded Investment	1,515	3,546	1,274
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment	1,567	1,965	1,775
Loans, With no related allowance recorded, Interest Income Recorded	6	6	14
Loans, With no related allowance recorded,Cash Basis Interest Recorded	6	6	14
Loans, With related allowance recorded, Unpaid Principal Balance	2,890	1,338	3,209
Loans, With related allowance recorded, Recorded Investment	2,862	1,338	3,209
Loans, With related allowance recorded, Allowance for Loan Losses Allocated	253	220	325
Loans, With related allowance recorded, Average Recorded Investment	2,896	3,238	3,028
Loans, With related allowance recorded, Interest Income Recorded	33	33	130
Loans, With related allowance recorded, Cash Basis Interest Recorded	33	33	130
Loans, Unpaid Principal Balance	5,158	5,881	5,370
Loans, Recorded Investment	4,377	4,884	4,483
Loans, Allowance for Loan Losses Allocated	253	220	325
Loans, Average Recorded Investment	4,463	5,203	4,803
Loans, Interest Income Recorded	39	39	144
Loans, Cash Basis Interest Recorded	39	39	144
Automobile [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Land [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance		131
Loans, With no related allowance recorded, Recorded Investment		102
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment		102	68
One-To-Four-Family [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance	1,186	889	1,011
Loans, With no related allowance recorded, Recorded Investment	811	514	543
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment	854	514	541
Loans, With related allowance recorded, Unpaid Principal Balance	552	566	860
Loans, With related allowance recorded, Recorded Investment	552	566	860
Loans, With related allowance recorded, Allowance for Loan Losses Allocated	45	147	78
Loans, With related allowance recorded, Average Recorded Investment	554	568	588
Loans, With related allowance recorded, Interest Income Recorded	7	7	27
Loans, With related allowance recorded, Cash Basis Interest Recorded	7	7	27
Multi-Family [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance	802	2,870	811
Loans, With no related allowance recorded, Recorded Investment	627	2,518	636
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment	630	918	889
Loans, With no related allowance recorded, Interest Income Recorded	6	6	14
Loans, With no related allowance recorded,Cash Basis Interest Recorded	6	6	14
Loans, With related allowance recorded, Unpaid Principal Balance	2,338	772	2,349
Loans, With related allowance recorded, Recorded Investment	2,310	772	2,349
Loans, With related allowance recorded, Allowance for Loan Losses Allocated	208	73	247
Loans, With related allowance recorded, Average Recorded Investment	2,342	2,386	2,369
Loans, With related allowance recorded, Interest Income Recorded	26	26	103
Loans, With related allowance recorded, Cash Basis Interest Recorded	26	26	103
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance		236
Loans, With no related allowance recorded, Recorded Investment		198
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment		200	99
Loans, With related allowance recorded, Average Recorded Investment		284	71
Construction [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Home Equity Line of Credit [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Unpaid Principal Balance	280	417	339
Loans, With no related allowance recorded, Recorded Investment	77	214	95
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	0	0	0
Loans, With no related allowance recorded, Average Recorded Investment	83	231	178
Other Consumer [Member]
Financing Receivable, Impaired [Line Items]
Loans, With no related allowance recorded, Allowance for Loan Losses Allocated	$ 0	$ 0	$ 0

Impaired Financing Receivable Allowance For Loan Losses Allocated

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Impaired Financing Receivable With No Related Allowance For Loan Losses Allocated

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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