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Allowance for Loan Losses - Information Regarding Loans Modified under TDR (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Contracts
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contracts	1
Pre-modification outstanding recorded investment	$ 138
Post-modification outstanding recorded investment	$ 88
Real Estate Loans [Member] | Secured by 1-4 Family Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contracts	1
Pre-modification outstanding recorded investment	$ 138
Post-modification outstanding recorded investment	$ 88

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+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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