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Investment Securities (Details 3) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Components of the entity's net realized and unrealized investment gains,(losses), after-tax |  |  |
Net change in pre-tax unrealized gains (losses) on investments in unconsolidated affiliates | $ (63.6) | $ 72.7 | $ 192.7
Income taxes | 5.1 | 0.8 | (0.3)
Net change in unrealized gains (losses) from investments in unconsolidated affiliates | (58.5) | 73.5 | 192.4
Net unrealized foreign currency gains (losses) on investments | (90.1) | 102.9 | 185.1
Total investment gains (losses) recognized through other comprehensive income | (148.6) | 176.4 | 377.5
Change in net unrealized investment gains (losses), after-tax | 11.9 | (34.5) | 292.3
Net realized investment gains (losses), after-tax | 80.0 | 94.3 | (55.0)
Total investment gains (losses) recorded during the period, after-tax | (56.7) | 236.2 | 614.8
Level 3 Inputs |  |  |
Investment securities |  |  |
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments | (45.6) | 30.0 | 127.1
Fixed maturity investments. | Level 3 Inputs |  |  |
Investment securities |  |  |
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments | (12.2) | 10.2 | 47.3
Common equity securities | Level 3 Inputs |  |  |
Investment securities |  |  |
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments | (16.6) | (19.2) | 14.7
Convertible fixed maturities | Level 3 Inputs |  |  |
Investment securities |  |  |
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments |  |  | 0.1
Other long-term investments | Level 3 Inputs |  |  |
Investment securities |  |  |
Total pre-tax gains (losses) included in earnings attributable to unrealized investment gains (losses) for Level 3 investments | $ (16.8) | $ 39.0 | $ 65.0

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- Definition The after-tax aggregate of the change in unrealized holding gain (loss) and foreign currency gain (loss) included in earnings during the reporting period. + References No definition available. + Details
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