Fair Value Disclosures (Narrative Disclosures) (Details) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Fair Value Inputs, Assets, Quantitative Information
Foreclosed Properties - Supported by Level 3 Valuation	$ 0
Transfer to foreclosed properties	1,258,000	1,107,000	3,119,000
Level 1 to Level 2 Transfers, Assets	0
Level 2 to Level 1 Transfers, Assets	0
Level 1 to Level 2 Transfers, Liabilities	0
Level 2 to Level 1 Transfers, Liabilities	0
Net losses due to impairment valuation	119,000		621,000
Commercial paper	$ 4,000,000		$ 0
Minimum
Fair Value Inputs, Assets, Quantitative Information
Quantification of unobservable inputs for Level 3 values for impaired loans	13.00%
Maximum
Fair Value Inputs, Assets, Quantitative Information
Quantification of unobservable inputs for Level 3 values for impaired loans	100.00%

Foreclosed Properties - Supported by Level 3 Valuation

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- Definition

Quantification of unobservable inputs for Level 3 values for impaired loans

+ References

No definition available.

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- Definition

Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Topic 230

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bb)

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

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-Topic 230

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-Paragraph 28

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- Definition

Value of other real estate transferred to the entity's other real estate in noncash transactions.

+ References

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