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Investments in Unconsolidated Affiliates (Details 2) (Symetra, USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Y Year	Jun. 30, 2011	Dec. 31, 2011
Symetra
Investments in unconsolidated affiliates
Investments in and Advances to Affiliates, Balance, Shares	17.4		17.4		17.4
Investments in Unconsolidated Affiliates on Conversion of Warrants	9.5		9.5		9.5
Fair value of investment					$ 261.0
Estimated fair value of investment per share					$ 15
After-tax equity in losses of unconsolidated affiliates					45.9
Equity in net unrealized gains (losses)	29.4	87.7	29.4	87.7	136.6
Ownership interest (as a percent)	15.00%		15.00%
Difference between fair value and carrying amount					195.8
Term of amortization (in years)			30
Risk free interest rate (as a percent)			0.31%
After tax amortization through equity in earnings	0.6		1.6
After tax amortization through equity in net unrealized losses	3.0		6.0
Pre-tax unamortized basis difference	$ 187.5		$ 187.5
Volatility rate (as a percent)			36.50%
Expected life (in years)			2.08
Class of Warrant or Right Fair Value Assumptions Per Strike Price	$ 11.49		$ 11.49
Market Price Per Share	$ 12.62		$ 12.62

X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investments accounted for under the equity method of accounting as of the balance sheet date.

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-Publisher AICPA

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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- Definition

Balance held at close of period in number of shares.

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The time period during which a warrant is expected to be outstanding.

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Volatility assumption used in valuing warrants.

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- Definition

The strike price per share that is used in valuing warrants.

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The risk-free interest rate assumption that is used in valuing warrants.

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The dollar spread between the fair value and the carrying amount at the date the impariment was recognized.

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- Definition

Represents the equity in unrealized gains or losses from investments in unconsolidated affiliates.

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- Definition

Represents fair value per share of investments accounted for under the equity method of accounting as of the balance sheet date.

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- Definition

Represents the entity's after-tax loss from the impairment of Symetra common shares recorded in equity in losses.

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- Definition

Represents recognized after tax amortization through equity in earnings of unconsolidated affiliates.

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Represents recognized after tax amortization through equity in net unrealized losses from investments in unconsolidated affiliates.

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Represents additional shares of an unconsolidated affiliate to be obtained on conversion of warrants.

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Represents the market price per share.

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Represents the unamortized dollar spread between the fair value and the carrying amount at the date the impariment was recognized.

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