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Fair Value Measurements (Details 2) (Residential mortgage-backed securities, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Residential mortgage-backed securities
Reconciliation of activity for mortgage-backed securities on a net basis
Balance at the beginning of the period	$ 24,063us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesMember
Principal paydowns	(763)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesMember
Total unrealized losses included in:
Other comprehensive income	349us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesMember
Impairment realized	(227)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesMember
Balance at the end of the period	$ 23,422us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesMember

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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

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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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

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)(1a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

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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

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=36462937&loc=d3e19207-110258

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