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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
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 | 283,625,689 | 283,625,689
Accumulated other comprehensive income (loss), taxes | $ 32 | $ 8
Treasury stock, shares | 198,824,693 | 193,803,976
Non Variable Interest Entity [Member] |  |
Fixed-maturity securities held as available-for-sale, amortized cost | $ 3,122 | $ 3,601
Investments pledged as collateral, amortized cost | 14 | 46
Short-term investments, amortized cost | 332 | 241
Medium-term notes, financial instruments carried at fair value | 110 | 102
Variable Interest Entity Primary Beneficiary [Member] |  |
Investments held-to-maturity, fair value | 967 | 925
Variable interest entity notes, financial instruments carried at fair value | $ 1,120 | $ 480

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