Loans and the Allowance for Loan Losses - (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($) loan_grade loan	Dec. 31, 2014 USD ($) loan
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Mortgage and commercial loans discontinued past due period (in days)	90 days
Consumer and other retail loans charged-off past due period (in days)	120 days
Nonperforming loans charged-off past due period (in days)	90 days
Number of restructured loans \| loan	0	0
Restructured loans discontinued past due period	90 days	90 days
Allowance for loan losses attributable to restructured loans	$ 42,051	$ 42,289
Remaining availability under commitments to lend additional funds on restructured loans	6	6,000
Fair value of loans contractual principal cash flows amount	100,023
Fair value of loans contractual interest cash flows	249
Fair value of loans contractual interest payments	2,329
Fair value of loans contractual purchase discount	$ 41,594
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Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	5
Maximum
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	9
Maximum \| Pass
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	4
Maximum \| Substandard
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	9
Minimum
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	1
Minimum \| Pass
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	1
Minimum \| Substandard
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Loan grades range (loan grade) \| loan_grade	6
Restructured Loans
Loans and Allowance for Loan Losses (Additional Textual) [Abstract]
Outstanding balance of restructured loans	$ 14,200	11,392
Allowance for loan losses attributable to restructured loans	$ 1,343	$ 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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Fair value of loans contractual principal cash flows amount.

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Fair value of loans contractual purchase discount.

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- Definition

Fair value of loans future interest payments.

+ References

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Loan grades range.

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Loans and the allowance for loan losses.

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Mortgage and commercial loans discontinued past due period.

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- Definition

Nonperforming loans charged off past due period.

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- Definition

Number of Restructured Loans

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

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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 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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-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

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-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

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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 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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