Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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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

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

+ Details

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- Details

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- Details

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Loans - Loans by Class Modified as Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016 Loans	Sep. 30, 2015 Loans	Sep. 30, 2016 USD ($) Loans	Sep. 30, 2015 Loans	Dec. 31, 2015 Loans
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			15		16
Commercial, Industrial, and Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			7		8
Commercial Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			8		8
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0		0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0		0
Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0		0
Trouble Debt Restructuring [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans	1	0	1	0
Pre-Modification Outstanding Recorded Investment \| $			$ 109
Post-Modification Outstanding Recorded Investment \| $			$ 109
Trouble Debt Restructuring [Member] \| Commercial, Industrial, and Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			1
Pre-Modification Outstanding Recorded Investment \| $			$ 109
Post-Modification Outstanding Recorded Investment \| $			$ 109
Trouble Debt Restructuring [Member] \| Commercial Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0
Pre-Modification Outstanding Recorded Investment \| $			$ 0
Post-Modification Outstanding Recorded Investment \| $			$ 0
Trouble Debt Restructuring [Member] \| Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0
Pre-Modification Outstanding Recorded Investment \| $			$ 0
Post-Modification Outstanding Recorded Investment \| $			$ 0
Trouble Debt Restructuring [Member] \| Consumer [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0
Pre-Modification Outstanding Recorded Investment \| $			$ 0
Post-Modification Outstanding Recorded Investment \| $			$ 0
Trouble Debt Restructuring [Member] \| Credit Cards [Member]
Financing Receivable, Impaired [Line Items]
Number of Loans \| Loans			0
Pre-Modification Outstanding Recorded Investment \| $			$ 0
Post-Modification Outstanding Recorded Investment \| $			$ 0