Loans and the Allowance for Loan Losses (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Mortgage and commercial loans discontinued past due period	90 days
Consumer and other retail loans charged-off past due period	120 days
Nonperforming loans charged-off past due period	90 days
Restructured loans	$ 0	$ 0
Restructured loans discontinued past due period	90 days
Allowance for loan losses attributable to restructured loans	42,302	42,289
Remaining availability under commitments to lend additional funds on restructured loans	0	0
Fair value of loans contractual principal cash flows amount	90,475
Fair value of loans contractual interest cash flows	5,532
Fair value of loans contractual interest payments	2,354
Fair value of loans contractual purchase discount	27,734
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Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	5
Maximum
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	9
Maximum \| Pass
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	4
Maximum \| Substandard
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	9
Minimum
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	1
Minimum \| Pass
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	1
Minimum \| Substandard
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade)	6
Restructured Loans
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Outstanding balance of restructured loans	9,484	11,392
Allowance for loan losses attributable to restructured loans	$ 1,332	$ 1,547

Consumer and other retail loans charged off past due period.

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- Definition

Fair value of loans contractual interest cash flows.

+ References

No definition available.

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- Definition

Fair value of loans contractual principal cash flows amount.

+ References

No definition available.

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- Definition

Fair value of loans contractual purchase discount.

+ References

No definition available.

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- Definition

Fair value of loans future interest payments.

+ References

No definition available.

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- Definition

Loan grades range.

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- Definition

Mortgage and commercial loans discontinued past due period.

+ References

No definition available.

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- Definition

Nonperforming loans charged off past due period.

+ References

No definition available.

+ Details

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- Definition

Maximum duration past due for restructured loans to be considered performing.

+ References

No definition available.

+ Details

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- Definition

Restructured loans equal to greater than ninety days past due.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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