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Investment Securities (Investments Held on Deposit or as Collateral) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2012 | Dec. 31, 2011
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Investments, Debt and Equity Securities [Abstract] |  |
Investments held in trusts | $ 169.9 | $ 79.2
Assets held by insurance regulators | $ 319.3 | $ 313.4

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- Definition Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 320 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6485772&loc=d3e22002-158495 + Details
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- Details
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- Definition Investments Held In Trusts + References No definition available. + Details
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