Investment Income Participation Fund Account Assets

No definition available.

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- Definition

A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(a),(b))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a, b

-Article 5

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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 Investment Income (Detail) (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
Net Investment Income
Investment Income, Interest and Dividend									$ 2,536.3	$ 2,552.1	$ 2,574.3
Less Investment Expenses									29.0	29.5	26.9
Less Investment Income on PFA Assets									15.1unm_InvestmentIncomeOnPfaAssets	15.7unm_InvestmentIncomeOnPfaAssets	16.1unm_InvestmentIncomeOnPfaAssets
Less Amortization of Tax Credit Partnerships									14.8us-gaap_IncomeTaxCreditsAndAdjustments	14.8us-gaap_IncomeTaxCreditsAndAdjustments	16.1us-gaap_IncomeTaxCreditsAndAdjustments
Net Investment Income	629.4us-gaap_NetInvestmentIncome	606.4us-gaap_NetInvestmentIncome	629.1us-gaap_NetInvestmentIncome	612.5us-gaap_NetInvestmentIncome	629.4us-gaap_NetInvestmentIncome	615.5us-gaap_NetInvestmentIncome	626.1us-gaap_NetInvestmentIncome	621.1us-gaap_NetInvestmentIncome	2,477.4us-gaap_NetInvestmentIncome	2,492.1us-gaap_NetInvestmentIncome	2,515.2us-gaap_NetInvestmentIncome
Fixed Maturity Securities
Net Investment Income
Investment Income, Interest and Dividend									2,344.4	2,371.6	2,404.0
Derivatives
Net Investment Income
Investment Income, Interest and Dividend									40.4	35.2	28.9
Mortgage Loans
Net Investment Income
Investment Income, Interest and Dividend									109.8	109.2	107.1
Policy Loans
Net Investment Income
Investment Income, Interest and Dividend									16.3	15.7	14.8
Other Long-term Investments
Net Investment Income
Investment Income, Interest and Dividend									23.0	18.0	15.2
Short-term Investments
Net Investment Income
Investment Income, Interest and Dividend									$ 2.4	$ 2.4	$ 4.3