Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Other than Temporary Impairment Losses, Investments, Portion in Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent	$ 0	$ 0
Other Comprehensive Income [Abstract]
Unrealized gains on available-for-sale securities, taxes	(1,871)	(1,628)
Unamortized holding losses on held to maturity securities transferred from available for sale, taxes	(57)	0
Other Comprehensive Income Loss Reclassification Adjustment For Sale Or Writedown Of Securities Included In Net Income Tax	$ 89	$ 74

Tax effect of the income statement impact of the reclassification adjustment for unrealized gain (loss) realized upon the sale or write-down of available-for-sale securities.

No definition available.

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) related to transfers of securities into the held-to-maturity and out of the available-for-sale category.

+ References

No definition available.

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- Definition

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (e,f)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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- Definition

Amount before tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34D

-URI http://asc.fasb.org/extlink&oid=27723805&loc=SL6284304-111560

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 35

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25362-111560

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