Investments - Roll-forward of OTTI (Details) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($)
Gross Other-Than-Temporary Impairments
Gross Other-Than-Temporary Impairments, Beginning Balance	$ (986)
Changes for credit losses on securities for which an OTTI was not previously recognized	(180)
Principal received on OTTI security	28
Gross Other-Than-Temporary Impairments, Ending Balance	(1,138)
Other-Than-Temporary Impairments Included in Other Comprehensive Loss
Other-Than Temporary Impairments Included in Other Comprehensive Income, Beginning Balance	(433)
Changes for credit losses on securities for which an OTTI was not previously recognized	(180)
Principal received on OTTI security	28
Other-Than Temporary Impairments Included in Other Comprehensive Income, Ending Balance	(585)
Net Other-Than Temporary Impairments Included in Retained Earnings
Net Other-Than Temporary Impairments Included in Retained Earnings, Beginning Balance	(553)
Changes for credit losses on securities for which an OTTI was not previously recognized	0
Principal received on OTTI security	0
Net Other-Than Temporary Impairments Included in Retained Earnings, Ending Balance	$ (553)

Accumulated Other Comprehensive Loss, Other Than Temporary Impairment Not Credit Loss, Pre-Tax Debt Securities

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- Definition

Other than Temporary Impairment Losses, Non-Credit losses Portion in Other Comprehensive Income (Loss)

+ References

No definition available.

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- Definition

Other than Temporary Impairment, Non-Credit Losses Recognized in Earnings, Additions, No Previous Impairment

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment, Non-Credit Losses Recognized in Retained Earnings, Additions, No Previous Impairment

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Gross [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment, Non-Credit Losses Included in Retained Earnings, Reductions, Principal Received

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment, Non-Credit Losses Recognized in Earnings, Reductions, Principal Received

+ References

No definition available.

+ Details

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- Definition

Other than Temporary Impairment, Non-Credit Losses Recognized in Other Comprehensive Income (Loss), Reductions, Principal Received

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Total of accumulated other comprehensive loss related to that portion of other than temporary impairment (OTTI) due to factors other than credit losses on debt securities categorized either as available-for-sale or held-to-maturity that an entity does not intend to sell and which it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis of the debt security. The amount represented by this item is net of tax, as applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

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- Definition

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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27340-111563

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