Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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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.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Derivative Instruments and Hedging Activities - Effect of Derivative Instruments on Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of income (loss) recognized in earnings	$ 1,876	$ 262	$ 951
Not Designated as Hedging Instrument \| Other non-interest income \| Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Amount of income (loss) recognized in earnings	1,889	550	711
Not Designated as Hedging Instrument \| Other non-interest income \| Credit contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of income (loss) recognized in earnings	(15)	(91)
Not Designated as Hedging Instrument \| Mortgage loan and banking income \| Residential mortgage loan commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of income (loss) recognized in earnings	2	(197)	$ 240
Designated as Hedging Instrument \| Interest Rate Swap \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in OCI on derivatives (effective portion)	(1,534)	(1,264)
Designated as Hedging Instrument \| Interest expense \| Interest Rate Swap \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) reclassified from accumulated OCI into income (effective portion)	$ 0	$ 0