Investment Income Participation Fund Account Assets

No definition available.

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- Definition

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

+ References

+ Details

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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 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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

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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 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 944
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-16(Column G))
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Investments Investment Income (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net Investment Income
Investment Income, Interest and Dividend									$ 2,498.6	$ 2,505.1	$ 2,527.0
Less Investment Expenses									32.8	31.9	31.2
Less Investment Income on PFA Assets									14.1	14.2	14.6
Net Investment Income	$ 619.8	$ 609.0	$ 620.5	$ 602.4	$ 617.9	$ 611.4	$ 623.3	$ 606.4	2,451.7	2,459.0	2,481.2
Fixed Maturity Securities
Net Investment Income
Investment Income, Interest and Dividend									2,271.8	2,293.9	2,327.1
Derivatives
Net Investment Income
Investment Income, Interest and Dividend									56.4	49.8	44.2
Mortgage Loans
Net Investment Income
Investment Income, Interest and Dividend									104.2	114.0	114.0
Policy Loans
Net Investment Income
Investment Income, Interest and Dividend									17.9	17.3	16.7
Other Long-term Investments
Net Investment Income
Investment Income, Interest and Dividend									37.0	22.6	21.6
Short-term Investments
Net Investment Income
Investment Income, Interest and Dividend									$ 11.3	$ 7.5	$ 3.4