Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Derivative Financial Instruments
Liability derivatives, Fair value	$ 131,272	$ 138,012
Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	518,688	490,417
Asset derivatives, Fair value	8,479	9,127
Liability derivatives, Fair value	8,342	9,444
Interest rate swap contracts
Derivative Financial Instruments
Asset derivatives, Fair value	8,458	9,492
Liability derivatives, Fair value	8,614	9,669
Interest rate swap contracts \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	482,862	459,508
Asset derivatives, Fair value	8,186	9,125
Liability derivatives, Fair value	8,342	9,302
Loan commitments \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	13,776	11,109
Asset derivatives, Fair value	89	2
Liability derivatives, Fair value	0	0
Forward contracts - mortgage loan \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	22,050	19,800
Asset derivatives, Fair value	204	0
Liability derivatives, Fair value	$ 0	$ 142

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226000-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 860

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4D

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=51814546&loc=SL51823488-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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+ References

No definition available.

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