Closing stock price

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- Definition

Number of Incentive Compensation Plans

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Expiration Term

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Weighted Average Grant Date Fair Value

+ References

No definition available.

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- Definition

The weighted average period between the balance-sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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SHARE-BASED COMPENSATION - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of long-term incentive compensation plans	2afl_NumberOfIncentiveCompensationPlans
Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Grant Date Fair Value	$ 16.24	14.25	16.84
Closing common stock price	$ 61.09afl_ClosingStockPrice
Aggregate intrinsic value of stock options outstanding	$ 116
Options Outstanding - Weighted-Average Remaining Term (Yrs)	4 years 6 months
Aggregate intrinsic value of stock options exercisable	103
Weighted-average remaining term of stock options exercisable (in years)	3 years 7 months 6 days
Stock Option Plan Effective Until February 2007 Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan, term (in years)	10 years
Second Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Stock option plan, vesting period	3 years
Shares available for future grants under the long-term incentive plan	11,200,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	45
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,880,000	1,671,000	1,363,000	1,350,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 2 months 12 days
Performance Based Vesting Condition Member \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	$ 20
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	849,000