Loans - Average Recorded Investment and Interest Income Recognized on Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	$ 130,371	$ 139,876	$ 133,432	$ 144,314
Interest Income Recognized	976	1,518	2,128	2,680
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	24,157	25,530	26,244	26,898
Interest Income Recognized	194	211	434	457
Commercial real estate loans
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	80,221	87,173	81,211	91,161
Interest Income Recognized	528	1,020	1,215	1,656
Commercial real estate loans \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	70,194	75,688	71,296	77,098
Interest Income Recognized	475	894	1,114	1,380
Commercial real estate loans \| Construction
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	10,027	11,485	9,915	14,063
Interest Income Recognized	53	126	101	276
Residential mortgage
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	22,922	22,566	23,262	22,206
Interest Income Recognized	234	249	436	499
Consumer
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	3,071	4,607	2,715	4,049
Interest Income Recognized	20	38	43	68
Consumer \| Home equity
Accounts, Notes, Loans and Financing Receivable
Average Recorded Investment	3,071	4,607	2,715	4,049
Interest Income Recognized	$ 20	$ 38	$ 43	$ 68

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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=66008989&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=66008989&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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