Consolidated Balance Sheets (Parenthetical - equity) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
AIG shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 5	$ 0
Preferred stock, shares authorized	100,000,000	0
Preferred stock, shares issued	20,000	0
Preferred stock liquidation preference	$ 500	$ 0
Common stock, par value (in dollars per share)	$ 2.5	$ 2.5
Common stock, shares authorized	5,000,000,000	5,000,000,000
Common stock, shares issued	1,906,671,492	1,906,671,492
Treasury stock, shares of common stock	1,036,934,591	1,040,062,063

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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.

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The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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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