Loans - Pre-Modification and Post-Modification Outstanding Recorded Investments (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) Contract	Sep. 30, 2015 USD ($) Contract	Sep. 30, 2016 USD ($) Contract	Sep. 30, 2015 USD ($) Contract
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	12	7	28	26
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 10,235	$ 7,584	$ 24,481	$ 20,196
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 10,291	$ 6,031	$ 23,680	$ 18,652
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	7	2	12	12
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 6,389	$ 1,530	$ 11,700	$ 4,621
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 6,248	$ 1,530	$ 11,088	$ 4,081
Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	3	2	6	7
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 3,745	$ 4,974	$ 10,404	$ 12,036
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 3,948	$ 3,451	$ 10,252	$ 11,079
Commercial real estate loans \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	1	0	4	4
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 1,667	$ 0	$ 8,325	$ 6,562
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 1,870	$ 0	$ 8,174	$ 6,444
Commercial real estate loans \| Construction
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	2	2	2	3
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 2,078	$ 4,974	$ 2,079	$ 5,474
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 2,078	$ 3,451	$ 2,078	$ 4,635
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	1	3	8	6
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 78	$ 1,080	$ 2,300	$ 2,458
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 77	$ 1,050	$ 2,271	$ 2,420
Consumer
Accounts, Notes, Loans and Financing Receivable
Troubled Debt Restructurings, Number of Contracts (in contract) \| Contract	1	0	2	1
Troubled Debt Restructurings, Pre-Modification Outstanding Recorded Investment	$ 23	$ 0	$ 77	$ 1,081
Troubled Debt Restructurings, Post-Modification Outstanding Recorded Investment	$ 18	$ 0	$ 69	$ 1,072

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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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