Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	9 Months Ended	3 Months Ended
Sep. 30, 2013 item	Sep. 30, 2012 item	Sep. 30, 2013 U.S. States and political subdivisions securities	Sep. 30, 2012 U.S. States and political subdivisions securities
Changes in the fair value of assets measured on a recurring basis
Balance at the beginning of the period			$ 5,452	$ 8,143
Total gains or losses (realized/unrealized): included in other comprehensive income			56	72
Purchases			1,500
Maturities			(491)	(474)
Balance at the end of the period			6,517	7,741
Total gains or losses (realized/unrealized): included in earnings	0	0
Number of transfers between levels	0	1
Transfers of assets measured on a recurring basis from Level 1 into Level 2	0
Transfers of assets measured on a recurring basis from Level 2 into Level 1	0
Transfers of liabilities measured on a recurring basis from Level 1 into Level 2	0
Transfers of liabilities measured on a recurring basis from Level 2 into Level 1	$ 0

Represents number of transfers between levels during the period.

No definition available.

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- Definition

Maturities that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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).

+ References

+ Details

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- Definition

Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

+ Details

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- Definition

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.

+ 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 (c)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-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.

+ Details

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