Derivative Financial Instruments - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014 InterestRateSwap
Derivative [Line Items]
Estimated amount to be transferred from OCI to earnings	$ 1,346
Termination value of derivatives in a net liability position	8,823
Derivative collateral posted	10,031
Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount of interest rate derivatives	137,186
Federal Home Loan Bank advances
Derivative [Line Items]
Number of debt instruments held	3
Cash Flow Hedging \| Interest Rate Swap
Derivative [Line Items]
Number of interest rate derivatives held	5	5
Notional amount of interest rate derivatives	56,000	56,000
Cash Flow Hedging \| Interest Rate Swap \| Federal Home Loan Bank advances
Derivative [Line Items]
Notional amount of interest rate derivatives	30,000
Cash Flow Hedging \| Interest Rate Swap \| Trust Preferred Securities
Derivative [Line Items]
Notional amount of interest rate derivatives	26,000
Cash Flow Hedging \| Interest rate cap
Derivative [Line Items]
Number of interest rate derivatives held	1	1
Notional amount of interest rate derivatives	13,000	13,000
Cash Flow Hedging \| Interest rate cap \| Trust Preferred Securities
Derivative [Line Items]
Notional amount of interest rate derivatives	$ 13,000

Number Of Debt Instruments Held

No definition available.

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- Definition

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

+ References

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

+ Details

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

+ Details

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

+ Details

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- Details

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

+ Details

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

+ Details

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- Details

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- Details

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- Details

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