Investments (Unrealized Losses) (Details)	Dec. 31, 2014 securities
Debt securities [Member]
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Gross unrealized losses, number of issues	190
Gross unrealized losses, percentage of total debt	14.50%
Gross unrealized losses, market value as a percent of amortized cost	97.80%
Gross unrealized losses, number of securities with maturities of 12 months or greater	148
Gross unrealized losses, number of securities with maturities of 12 months or greater (as a percentage)	77.50%
Equity Securities [Member]
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Gross unrealized losses, number of securities rated investment grade	16
Other-than-temporarily impaired securities, number of securities rated investment grade	4
External Credit Rating, Investment Grade [Member] \| Debt securities [Member]
Available-for-Sale Securities and Held-to-Maturity Securities [Line Items]
Gross unrealized losses, number of securities rated investment grade	186

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Available-for-sale Securities, Gross Unrealized Losses, Market Value of Bonds Percent of Amortized Cost

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- Definition

Available for Sale Securities, Gross Unrealized Losses, Number of Securities

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Available for Sale Securities, Gross Unrealized Losses, Number of Securities as a Percentage of Total Debt

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- Definition

Available-for-sale Securities, Gross Unrealized Losses, Number of Securities, Debt Maturities, Twelve Months or Greater

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Available-for-sale Securities, Gross Unrealized Losses, Number of Securities, Debt Maturities, Twelve Months or Greater, Percent of Total

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- Definition

Other than Temporary Impairment Losses, number of securities rated investment grade

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

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