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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Preferred stock, par value | $ 1 | $ 1
Preferred stock, authorized shares | 10,000,000 | 10,000,000
Preferred stock, issued | 0 | 0
Preferred stock, outstanding | 0 | 0
Common stock, par value | $ 1 | $ 1
Common stock, authorized shares | 400,000,000 | 400,000,000
Common stock, issued shares | 283,186,115 | 283,186,115
Accumulated other comprehensive income (loss), taxes | $ 8 | $ 8
Treasury stock, shares | 228,780,540 | 229,508,967
Non Variable Interest Entity [Member] |  |
Fixed-maturity securities held as available-for-sale, amortized cost | $ 2,016 | $ 2,078
Investments pledged as collateral, amortized cost | 2 | 6
Short-term investments, amortized cost | 418 | 281
Premiums receivable (net of allowance for credit losses) | 5 | 5
Medium-term notes, financial instruments carried at fair value | 105 | 110
Variable Interest Entity Primary Beneficiary [Member] |  |
Variable interest entity notes, financial instruments carried at fair value | $ 321 | $ 350

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