Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

+ Details

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Balance Type:	debit
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Loans - Schedule of Legacy Loans on Nonaccrual Status (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	$ 50,928	$ 34,970
Interest income if non-accrual loans had been current	2,100	1,800	$ 2,900
Commercial Loans \| Commercial Real Estate - Construction
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	120	69
Commercial Loans \| Commercial Real Estate - Other
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	15,422	6,859
Commercial Loans \| Commercial and Industrial
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	6,659	3,025
Commercial Loans \| Energy-Related
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	7,081	27
Residential Mortgage \| Residential Mortgage
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	13,674	14,362
Consumer and Other Loans \| Consumer - Home Equity
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	5,628	7,404
Consumer and Other Loans \| Consumer - Indirect Automobile
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	1,181	1,419
Consumer and Other Loans \| Consumer - Credit Card
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	394	1,032
Consumer and Other Loans \| Consumer - Other
Financing Receivable, Recorded Investment, Past Due
Total loans on nonaccrual status	$ 769	$ 773