SHAREHOLDERS' EQUITY - Reconciliation of Number of Shares of Common Stock (Detail) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Common Stock Issued [Roll Forward]
Balance, beginning of period	668,132us-gaap_CommonStockSharesIssued	667,046us-gaap_CommonStockSharesIssued
Exercise of stock options and issuance of restricted shares	722	574
Balance, end of period	668,854us-gaap_CommonStockSharesIssued	667,620us-gaap_CommonStockSharesIssued
Treasury Stock [Roll Forward]
Balance, beginning of period	225,687us-gaap_TreasuryStockShares	207,633us-gaap_TreasuryStockShares
Balance, end of period	235,083us-gaap_TreasuryStockShares	213,592us-gaap_TreasuryStockShares
Shares outstanding, end of period	433,771us-gaap_CommonStockSharesOutstanding	454,028us-gaap_CommonStockSharesOutstanding
Treasury Stock
Treasury Stock [Roll Forward]
Stock Acquired In Open Market, Shares	9,827	6,535
Other purchases	162	110
Shares issued to AFL Stock Plan	(295)	(284)
Exercise of stock options	(192)	(281)
Other dispositions	(106)	(121)

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Other additions to number of shares during period.

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Number of shares that have been repurchased from the open market during the period

+ References

No definition available.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (SX 210.5-02.29)

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Name Regulation S-X (SX)

-Number 210

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- Definition

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Number of shares of stock issued during the period that is attributable to transactions involving issuance of stock not separately disclosed.

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No definition available.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Number of share options (or share units) exercised during the current period.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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