Investment losses incurred on operating losses from tax advantaged assets.

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- Definition

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.1-5)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 1, 2 , 3, 4, 5

-Article 9

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- Definition

Amount of expenses related to the generation of investment income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.2)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.9)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.2)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 2

-Article 7

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Investments (Net Investment Income Summarized By Investment Type) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Summary Of Investment Income [Line Items]
Investment income									$ 642.7	$ 666.7	$ 664.1
Investment expenses									(22.4)	(22.9)	(22.3)
Tax-advantaged investment operating losses									(19.4)	(13.9)	(13.3)
Net investment income	153.4us-gaap_NetInvestmentIncome	147.1us-gaap_NetInvestmentIncome	149.8us-gaap_NetInvestmentIncome	150.6us-gaap_NetInvestmentIncome	160.8us-gaap_NetInvestmentIncome	155.8us-gaap_NetInvestmentIncome	154.1us-gaap_NetInvestmentIncome	159.2us-gaap_NetInvestmentIncome	600.9us-gaap_NetInvestmentIncome	629.9us-gaap_NetInvestmentIncome	628.5us-gaap_NetInvestmentIncome
Total Fixed Maturity Securities [Member]
Summary Of Investment Income [Line Items]
Investment income									296.4	303.0	316.8
S And P Five Hundred Index Options [Member]
Summary Of Investment Income [Line Items]
Investment income									8.6	14.4	7.8
Commercial Mortgage Loans [Member]
Summary Of Investment Income [Line Items]
Investment income									332.1	341.7	331.9
Total Real Estate [Member]
Summary Of Investment Income [Line Items]
Investment income									1.1	(1.4)	(1.0)
Other Investment Classification [Member]
Summary Of Investment Income [Line Items]
Investment income									$ 4.5	$ 9.0	$ 8.6