Fair Value Measurements and Fair Value of Financial Instruments (Additional Qualitative Information about Level 3 Assets) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2013	Dec. 31, 2012
Impaired Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 9,369	$ 11,616
Fair Value Measurements, Valuation Techniques	Appraisal of collateral(1)	Appraisal of collateral(1)
Fair Value Disclosure, Unbservable Input Range	Appraisal adjustments(2)	Appraisal adjustments(2)
Impaired Loans [Member] \| Minimum [Member] \| Unobservable Inputs Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	10.00%	0.00%
Impaired Loans [Member] \| Maximum [Member] \| Unobservable Inputs Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate		30.00%
Impaired Loans [Member] \| Weighted Average [Member] \| Unobservable Inputs Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	10.00%	24.10%
Foreclosed Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 993	$ 852
Fair Value Measurements, Valuation Techniques	Appraisal of collateral(1)	Appraisal of collateral(1)
Fair Value Disclosure, Unbservable Input Range	Liquidation Expenses(2)	Liquidation Expenses(2)
Foreclosed Real Estate Owned [Member] \| Minimum [Member] \| Unobservable Inputs - Liquidation Expenses [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	10.00%	20.00%

Fair Value Disclosure, Unbservable Input Range

No definition available.

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

+ Details

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- Details

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

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- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ References

+ Details

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