Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	$ 542,796	$ 490,417
Asset derivatives, Fair value	11,615	9,127
Liability derivatives, Fair value	11,959	9,444
Interest rate swap contracts
Derivative Financial Instruments
Asset derivatives, Fair value	11,870	9,492
Interest rate swap contracts \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	507,513	459,508
Asset derivatives, Fair value	11,583	9,125
Liability derivatives, Fair value	11,806	9,302
Loan commitments \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	16,181	11,109
Asset derivatives, Fair value	32	2
Liability derivatives, Fair value	0	0
Forward contracts - mortgage loan \| Non-hedging derivative financial instruments
Derivative Financial Instruments
Notional or contractual amount	19,102	19,800
Asset derivatives, Fair value	0	0
Liability derivatives, Fair value	$ 153	$ 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

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-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

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-Name Accounting Standards Codification

-Topic 210

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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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