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Consolidated Balance Sheets - (Parenthetical) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
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Statement of Financial Position [Abstract] |  |
Fixed maturities securities at amortized cost | $ 39,952 | $ 38,953
Marketable securities fixed maturities allowance for credit loss | 18 | 40
Equity securities at cost | 964 | 941
Mortgage loans on real estate commercial and consumer allowance for credit loss | 16 | 26
Allowance for uncollectible reinsurance | 21 | 21
Allowance for uncollectible insurance receivables | 29 | 33
Accumulated depreciation on property and equipment | 255 | 231
Due to related parties | $ 56 | $ 89
Common stock, par value (in usd per share) | $ 2.50 | $ 2.50
Common stock, shares authorized (in shares) | 500,000,000 | 500,000,000
Common stock, shares issued (in shares) | 273,040,243 | 273,040,243
Common stock, shares outstanding (in shares) | 271,363,999 | 271,391,603
Treasury stock, shares (in shares) | 1,676,244 | 1,648,640

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