Loans - Summary of Information Related to Average Balances of Impaired Loans and Interest Income Recognized (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 6,125	$ 11,288
Interest Income Recognized	212	552
Cash Basis Interest Recognized	58	139
Residential Real Estate [Member] \| One-to-Four Family [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	4,738	5,981
Interest Income Recognized	158	239
Cash Basis Interest Recognized	56	92
Residential Real Estate [Member] \| Home Equity Loans and Lines of Credit [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	260	71
Interest Income Recognized	1	3
Cash Basis Interest Recognized	1	1
Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	1,122	5,219
Interest Income Recognized	51	309
Cash Basis Interest Recognized		45
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5	17
Interest Income Recognized	2	1
Cash Basis Interest Recognized	$ 1	$ 1

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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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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+ References

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