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Consolidated Balance Sheet (Unaudited) (Parenthetical) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Investment securities, available for sale, amortized cost | $ 12,397 | $ 10,691
Investment securities, held to maturity, fair value | 13,865 | 14,308
Equity and other securities, cost | 1,279 | 1,125
Loans and leases, unearned discount | $ 928 | $ 868
Preferred stock, par value | $ 1 | $ 1
Preferred stock, shares authorized | 20,000,000 | 20,000,000
Preferred stock, shares issued | 10,000,000 | 10,000,000
Preferred stock, liquidation preference per share | $ 25 | $ 25
Common stock, par value | $ 0.50 | $ 0.50
Common stock, shares authorized | 250,000,000 | 250,000,000
Common stock, shares issued | 179,436,779 | 179,436,779
Common stock issuable, shares | 11,458 | 12,217
Treasury stock, common shares | 12,724,121 | 13,300,298
Series A Series C Series And E Preferred Stock [Member] |  |
Preferred stock, shares issued | 350,000 | 350,000
Preferred stock, shares outstanding | 350,000 | 350,000
Preferred stock, liquidation preference per share | $ 1,000 | $ 1,000
Series F And Series G Preferred Stock [Member] |  |
Preferred stock, shares issued | 140,000 | 140,000
Preferred stock, shares outstanding | 140,000 | 140,000
Preferred stock, liquidation preference per share | $ 10,000 | $ 10,000

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