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Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
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Consolidated Balance Sheets (Parentheticals) [Line Items] |  |
Fixed income securities, held-to-maturity, fair value | $ 20,213 | $ 21,975
Fixed income securities, available-for-sale, allowance for credit losses | 7,180 | 0
Fixed income securities, available-for-sale, amortized cost | 6,097,973 | 5,879,986
Commercial mortgage loan, fair value | 30,595 |
Equity Securities, cost | 158,045 | 72,061
Property and equipment, accumulated depreciation and amortization | $ 240,057 | $ 227,566
Preferred stock, par value per share | $ 0 | $ 0
Preferred stock, shares authorized | 5,000,000 | 5,000,000
Preferred stock, shares issued | 0 | 0
Preferred Stock, Shares Outstanding | 0 | 0
Common stock, par value per share | $ 2 | $ 2
Common stock, shares authorized | 360,000,000 | 360,000,000
Common stock, shares issued | 103,961,596 | 103,484,159
Treasury stock, shares | 44,126,894 | 44,023,006

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