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Unaudited Condensed Consolidated Balance Sheets (Parenthetical) | Jun. 30, 2020 $ / shares shares | Dec. 31, 2019 $ / shares shares
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Class A Common Stock |  |
Common stock, par value (in dollars per share) | $ / shares | $ 1 | $ 1
Common stock, shares outstanding (in shares) | shares | 5,463,761 | 5,397,458
Class B Common Stock |  |
Common stock, par value (in dollars per share) | $ / shares | $ 1 | $ 1
Common stock, convertible conversion ratio | 1 | 1
Common stock, shares outstanding (in shares) | shares | 1,568,550 | 1,568,670

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