Unaudited Consolidated Balance Sheets (Parentheticals) - USD ($) shares in Millions, $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Available for sale securities, amortized cost	$ 25,562	$ 22,615
Allowance for credit losses on investments	57	41
Allowance for credit losses on premiums receivable	34	35
Allowance for credit losses on reinsurance recoverable	23	22
Allowance for credit losses on contractholder receivable	$ 3	$ 3
Common shares, par value per share	$ 0.0011	$ 0.0011
Common shares issued (shares)	591.4	588.3
Common shares held in treasury (shares)	218.3	217.9
Fixed maturities
Available for sale securities, amortized cost	$ 23,882	$ 21,282
Allowance for credit losses on investments	57	41
Short-term investments
Available for sale securities, amortized cost	1,680	1,333
Allowance for credit losses on investments	$ 0	$ 0

Amount of allowance for credit loss on contractholder receivables.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Face amount or stated value per share of common stock.

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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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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

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Amount of allowance for credit loss on reinsurance recoverable.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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