Loans - Average Recorded Investment and Interest Income Recognized on Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	$ 136,493	$ 148,803
Interest Income Recognized	1,152	1,162
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	28,331	28,282
Interest Income Recognized	240	246
Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	82,200	95,193
Interest Income Recognized	687	636
Commercial real estate loans \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	72,398	78,523
Interest Income Recognized	639	486
Commercial real estate loans \| Construction
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	9,802	16,670
Interest Income Recognized	48	150
Consumer
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	2,359	3,485
Interest Income Recognized	23	30
Consumer \| Home equity
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	2,359	3,485
Interest Income Recognized	23	30
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	23,603	21,843
Interest Income Recognized	$ 202	$ 250

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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=49124121&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=49124121&loc=d3e5258-111524

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- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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