The income earned from investments in securities and property, equipment and other capital assets. It includes rent from property and equipment, dividends from shares in corporations, and interest from bonds, loans, mortgages, derivatives, commercial paper, bank accounts, certificates of deposits, treasuries, and other financial securities, before the deduction of investment expenses. It does not include realized gains and losses on investments.

No definition available.

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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 - Components of Net 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
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									$ 3,399afl_GrossInvestmentIncome	$ 3,371afl_GrossInvestmentIncome	$ 3,520afl_GrossInvestmentIncome
Less investment expenses									80	78	47
Net investment income	808us-gaap_NetInvestmentIncome	841us-gaap_NetInvestmentIncome	843us-gaap_NetInvestmentIncome	827us-gaap_NetInvestmentIncome	826us-gaap_NetInvestmentIncome	821us-gaap_NetInvestmentIncome	813us-gaap_NetInvestmentIncome	833us-gaap_NetInvestmentIncome	3,319us-gaap_NetInvestmentIncome	3,293us-gaap_NetInvestmentIncome	3,473us-gaap_NetInvestmentIncome
Fixed Maturities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									3,249	3,210	3,248
Perpetual securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									141	153	253
Equity securities
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									7	7	17
Short Term Investments and Cash Equivalents
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income									$ 2	$ 1	$ 2