Derivatives and Hedging Activities - Derivatives not designated as hedging instruments under ASC 815 (Details 1) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	$ 25,463	$ 20,051
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	29,364	26,656
Derivative assets \| Customer swap positions
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	16,018	6,185
Derivative assets \| Dealer offsets to customer swap positions
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value		31
Derivative assets \| Mortgage banking - loan commitment
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	1,072	188
Derivative assets \| Mortgage banking - forward sales commitment
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	3	1
Derivative assets \| Bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	3,793	9,230
Derivative assets \| Offsetting positions for de-designated cash flow hedges
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, assets at fair value	4,577	4,416
Derivative liabilities \| Customer swap positions
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value		31
Derivative liabilities \| Dealer offsets to customer swap positions
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	16,170	6,339
Derivative liabilities \| Risk participations
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	38
Derivative liabilities \| Mortgage banking - forward sales commitment
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	70	22
Derivative liabilities \| Dealer offsets to bifurcated embedded derivatives
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	8,507	15,794
Derivative liabilities \| De-designated cash flow hedges
Derivatives, Fair Value [Line Items]
Interest rate derivative instruments not designated as hedging instruments, liabilities at fair value	$ 4,579	$ 4,470

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Fair value as of the balance sheet date of all derivative assets not designated 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 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

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Fair value as of the balance sheet date of all derivative liabilities not designated as hedging instruments.

+ References

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