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Loans - Troubled Debt Restructurings (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Financing Receivable, Modifications [Line Items]
Balance at time of restructuring	$ 709	$ 6,874
Balance at period end	584	6,741
Commercial and industrial, Energy [Member]
Financing Receivable, Modifications [Line Items]
Balance at time of restructuring	0	0
Balance at period end	0	0
Commercial and industrial, Other commercial [Member]
Financing Receivable, Modifications [Line Items]
Balance at time of restructuring	709	3,752
Balance at period end	584	3,672
Commercial real estate, Buildings, land and other [Member]
Financing Receivable, Modifications [Line Items]
Balance at time of restructuring	0	3,122
Balance at period end	$ 0	$ 3,069

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- Definition

Post-modification amount of investment in financing receivables 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



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+ References

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-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



-Section 50



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