Allowance for Credit Losses - Loan Portfolio by Impairment Methodology (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans	$ 391,272	$ 395,771
Ending balance: individually evaluated for impairment	16,340	17,105
Ending balance: collectively evaluated for impairment	374,932	378,666
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans	101,395	104,555
Ending balance: individually evaluated for impairment	1,809	2,405
Ending balance: collectively evaluated for impairment	99,586	102,150
Real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans	242,505	237,938
Ending balance: individually evaluated for impairment	12,724	12,868
Ending balance: collectively evaluated for impairment	229,781	225,070
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans	47,372	53,278
Ending balance: individually evaluated for impairment	1,807	1,832
Ending balance: collectively evaluated for impairment	$ 45,565	$ 51,446

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The balance of financing receivables that were collectively evaluated for impairment.

+ 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 (h)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953423-111524

+ Details

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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- Definition

Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ 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 210.9-03.10(3))

-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 10

-Subparagraph 3

-Article 9

+ Details

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