Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Fair value portion of investments accounted under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6903542&loc=d3e32014-111567

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- Definition

Number of shares of affiliates held for management investment companies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 6

-Subparagraph (SX 210.12-14.Column B)

-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611322-123010

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column B

-Article 12

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

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- Definition

Represents the period over which basis difference amortized.

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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.

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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No definition available.

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Weight Average Years Remaining

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Investments in Unconsolidated Affiliates (Symetra) (Details) (Symetra, USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2011	Dec. 31, 2012
Investments in unconsolidated affiliates
Shares of Symetra Financial Corporation owned (in shares)	20.05			20.05
Ownership interest (as a percent)	17.27%			17.31%
Equity Method Investments Fair Value Per Share					$ 15
Term of amortization (in years)		30 years
Weight Average Years Remaining	28 years
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 165.7			$ 170.4
Common Stock
Investments in unconsolidated affiliates
Fair value of investment						261.0
Share Price	$ 23.46
equity in earnings of unconsolidated affiliates
Investments in unconsolidated affiliates
After tax amortization through equity in earnings	0.7		0.7
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	35.1			36.4
Net unrealized gains (losses) of unconsolidated affiliates
Investments in unconsolidated affiliates
After tax amortization through equity in net unrealized losses	2.8		2.9
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	$ 130.6			$ 134.0