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Unaudited Condensed Consolidated Balance Sheets (Parenthetical) | Sep. 30, 2021 $ / shares shares | Dec. 31, 2020 $ / 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 | 5,607,149 | 5,489,615
Class B Common Stock |  |
Common stock, par value (in dollars per share) | $ / shares | $ 1 | $ 1
Common stock, shares outstanding (in shares) | shares | 1,566,643 | 1,568,210
Common stock, convertible conversion ratio | 1 | 1

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