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Investments (Number of Securities in an Unrealized Unrecognized Loss Position) (Details) (USD $)	6 Months Ended												3 Months Ended
	Jun. 30, 2013 Securities	Dec. 31, 2012 Securities	Jun. 30, 2013 Eighty Percent to Ninety-Nine Percent [Member] Securities	Dec. 31, 2012 Eighty Percent to Ninety-Nine Percent [Member] Securities	Jun. 30, 2013 Sixty Percent to Seventy-Nine Percent [Member] Securities	Dec. 31, 2012 Sixty Percent to Seventy-Nine Percent [Member] Securities	Jun. 30, 2013 Forty Percent to Fifty-Nine Percent [Member] Securities	Dec. 31, 2012 Forty Percent to Fifty-Nine Percent [Member] Securities	Jun. 30, 2013 Twenty Percent to Thirty-Nine Percent [Member] Securities	Dec. 31, 2012 Twenty Percent to Thirty-Nine Percent [Member] Securities	Jun. 30, 2013 Zero Percent to Nineteen Percent [Member] Securities	Dec. 31, 2012 Zero Percent to Nineteen Percent [Member] Securities	Jun. 30, 2013 10 year U.S. Treasury Note [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized Unrecognized Losses Period Increase	$ (43,300,000)
Number of securities in an unrealized/unrecognized loss position	505	101	504	100	1	1	0	0	0	0	0	0
Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months	1,000,000	1,700,000
Increase in interest rate on the 10 year US treasury note													64
Unrealized Unrecognized Loss	46,260,000	2,934,000	46,022,000	2,701,000	238,000	233,000	0	0	0	0	0	0
Non-Credit OTTI Charges		$ 900,000
Decline in fair value percentage		5.00%

X

- Definition

Non-credit portion of other-than-temporary impairment losses on fixed maturity securities recognized in other comprehensive income that have been in a loss position for more than twelve months. This item includes subsequent changes to these securities such as amortization on HTM securities or subsequent sales. This item does not include subsequent changes in appreciation or loss in value.

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No definition available.

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- Definition

This item contains disclosure of the number of available-for-sale and held-to-maturity securities determined to be in an unrealized/unrecognized loss position.

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No definition available.

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- Definition

This item represents the percentage decline in fair value of fixed maturity securities compared to amortized cost that have been in a loss position for more than twelve months. This impairment has been determined to be temporary.

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No definition available.

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- Definition

Represents total unrealized and unrecognized losses of all available-for-sale and held-to-maturity securities in an unrealized and unrecognized loss position for more than 12 months as of the end of the period.

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No definition available.

+ Details

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- Definition

This item represents the sum of (i) the excess of amortized cost over fair value for available-for-sale securities that are in a loss position and (ii) the market fluctuations on held-to-maturity securities from the later of (a) the date a security is designated as held-to-maturity; or (b) the date that an other-than-temporary impairment charge is recognized on a held-to-maturity security for securities that are in an unrecognized loss position.

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No definition available.

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- Definition

Represents the increase or decrease in unrealized/unrecognized losses for available-for-sale and held-to-maturities securities

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No definition available.

+ Details

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- Definition

Increase in basis points of the stated interest rate on the debt instrument.

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No definition available.

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