Investments (Rollforward of The Amount of Other-Than-Temporary Impairments Related to Credit Losses Recognized in Earnings for Which a Portion of an Other-Than-Temporary Impairment was Recognized in Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investments [Abstract]
Portion of other-than-temporary impairments recognized in other comprehensive income (loss), before taxes	$ 0	$ 0	$ 52
Net other-than-temporary impairments recognized in earnings	0	0	(343)
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Balance, beginning	561	838
Additions:
Amount related to credit loss for which an other-than-temporary impairment was not previously recognized	0	0
Amount related to credit loss for which an other-than-temporary impairment was previously recognized	0	0
Reductions:
Securities sold during the period	(63)	(277)
Securities for which the amount previously recognized in other comprehensive income was recognized in earnings, because the Company intends to sell the security or is more likely than not the Company will be required to sell the security	0	0
Increases in cash flows expected to be collected that are recognized over the remaining life of the security	0	0
Balance, ending	$ 498	$ 561	$ 838

Investments (Rollforward of The Amount of Other-Than-Temporary Impairments Related to Credit Losses Recognized in Earnings for Which a Portion of an Other-Than-Temporary Impairment was Recognized in Accumulated Other Comprehensive Income) (Details) (USD $)
In Thousands, unless otherwise specified

12 Months Ended

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Investments [Abstract]

Portion of other-than-temporary impairments recognized in other comprehensive income (loss), before taxes

$ 0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities

$ 52us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities

Net other-than-temporary impairments recognized in earnings

0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities

(343)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities

Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]

Balance, beginning

561us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

838us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

Additions:

0us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment

0us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses

Reductions:

Securities sold during the period

(63)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold

(277)us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold

Securities for which the amount previously recognized in other comprehensive income was recognized in earnings, because the Company intends to sell the security or is more likely than not the Company will be required to sell the security

0us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsChangeInStatus

Increases in cash flows expected to be collected that are recognized over the remaining life of the security

0us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows

Balance, ending

$ 498us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

$ 561us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

$ 838us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

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This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held due to increases in cash flows expected to be collected and recognized over the remaining life of the security.

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Amount before tax of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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