SHARE-BASED COMPENSATION - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015 plan	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of long-term incentive compensation plans	2afl_NumberOfIncentiveCompensationPlans
Proceeds from Stock Options Exercised	$ 22	$ 18
Tax Benefit from Stock Options Exercised	15	11
Stock Option Plan Effective until February 2007
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]
Stock option plan, term (in years)	10 years
Stock option plan, vesting period	3 years
Shares available for future grants under the long-term incentive plan	10,100,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	64
Total compensation cost not yet recognized, restricted stock awards, weighted-average period (in years)	1 year 9 months 18 days
Performance based Vesting Condition \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized, restricted stock awards	$ 26
Total compensation cost not yet recognized, restricted stock awards, shares	780,000

Number of Incentive Compensation Plans

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ 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 (j)

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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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.

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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.

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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

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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

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