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Investment Securities (Details 3) (Level 3 Inputs, USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Investment securities
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments	$ 15.5	$ (7.6)
Fixed maturity investments.
Investment securities
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments	7.8	1.9
Common equity securities
Investment securities
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments	0.5	(1.8)
Other long-term investments
Investment securities
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments	$ 7.2	$ (7.7)

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- Definition

The aggregate increase (decrease) in the market value of unsold investments whose gains (losses) are included in earnings.

+ References

No definition available.

+ Details

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