Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014 item	Mar. 31, 2013 item
Changes in the fair value of assets measured on a recurring basis
Total gains or losses (realized/unrealized): included in earnings	$ 0	$ 0
Number of transfers between levels	0	0
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	5,498	7,701
Total gains or losses (realized/unrealized): included in other comprehensive income	16	(93)
Purchases	0	0
Issuances	0	0
Sales	0	0
Settlements	0	0
Maturities	(805)	(538)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance at the end of the period	$ 4,709	$ 7,070

Represents number of transfers between levels during the period.

No definition available.

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Amount of maturities of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB

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