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Loans - Impaired Loans Classified as Troubled Debt Restructured (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) Contract	Mar. 31, 2015 USD ($) Contract
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts Modified in the Last 3 Months | Contract		1
Pre-Modification Outstanding Recorded Investment		$ 28
Post-Modification Outstanding Recorded Investment		$ 24
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts Modified in the Last 3 Months | Contract		1
Pre-Modification Outstanding Recorded Investment		$ 528
Post-Modification Outstanding Recorded Investment		$ 430
Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts Modified in the Last 3 Months | Contract	1
Pre-Modification Outstanding Recorded Investment	$ 138
Post-Modification Outstanding Recorded Investment	$ 138

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Financing Receivable Modifications Subsequent Default Post Modification Recorded Investment

+ References

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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