Disclosures About Fair Value of Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Changes in fair value due to observable factors
Fair Value, January 1, Other Assets	$ 2,001	$ 1,554
Fair Value, January 1, Other Liabilities
Total realized gains included in income, Other Assets	242	61
Total realized gains included in income, Other Liabilities
Change in unrealized gains/losses included in other comprehensive income for assets and liabilities still held at December 31, Other Assets
Change in unrealized gains/losses included in other comprehensive income for assets and liabilities still held at December 31, Other Liabilities
Purchases, issuances and settlements, net, Other Assets	4,072	386
Purchases, issuances and settlements, net, Other Liabilities
Transfers out of Level 3, Other Assets
Transfers out of Level 3, Other Liabilities
Fair Value, December 31, Other Assets	6,315	2,001
Fair value December 31, Other Liabilities
Total realized gains included in income related to financial assets and liabilities still on the consolidated balance sheet at December 31

This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).

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Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Amount of gain (loss) recognized in other comprehensive income, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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- Definition

Amount of purchases, sales, issues, and settlements (net) which have taken place in relation to assets measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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-Number 157

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-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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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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

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Amount of gain (loss) recognized in other comprehensive income, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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

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Amount of purchases, sales, issues, and settlements in relation to liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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