Fair Value Measurements (Details 2) (Fair Value, Measurements, Nonrecurring [Member], Significant Unobservable Inputs (Level 3) [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Impaired loans Assets [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair value assets	$ 9,639	$ 7,944
Fair Value Measurements, Valuation Techniques	Property appraisals	Discounted appraised value
Selling cost	10.00%	10.00%
Fair Value Inputs, Discount for lack of marketability, Weighted average	3.00%
Other Real Estate Owned [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair value assets	$ 5,173	$ 5,590
Fair Value Measurements, Valuation Techniques	Property appraisals	Discounted appraised value
Selling cost	7.00%	7.00%
Fair Value Inputs, Discount for lack of marketability, Weighted average	1.00%
Minimum [Member] \| Impaired loans Assets [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair Value Inputs, Discount for lack of marketability	0.00%	0.00%
Minimum [Member] \| Other Real Estate Owned [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair Value Inputs, Discount for lack of marketability	0.00%	0.00%
Maximum [Member] \| Impaired loans Assets [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair Value Inputs, Discount for lack of marketability	29.00%	30.00%
Maximum [Member] \| Other Real Estate Owned [Member]
Quantitative information about Level 3 Fair Value Measurements
Fair Value Inputs, Discount for lack of marketability	20.00%	25.00%

Fair value inputs weighted average discount for lack of marketability and age of appraisal.

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 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

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Period Type:	instant

- Details

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- Definition

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ 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=7578670&loc=d3e19207-110258

+ 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=7578670&loc=d3e19207-110258

+ Details

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Period Type:	duration

- Definition

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

+ 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=7578670&loc=d3e19207-110258

+ Details

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