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CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares | 3 Months Ended | 6 Months Ended
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Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Statement of Stockholders' Equity [Abstract] |  |  |  |
Distribution of shares of treasury stock for employee restricted stock awards (in shares) |  |  |  | 255
Cash dividends declared (in dollars per share) | $ 0.31 | $ 0.26 | $ 0.57 | $ 0.52
Distribution of shares of treasury stock for directors' compensation (in shares) |  |  | 9,291 | 7,923
Distribution of shares of treasury stock for employee stock compensation (in shares) |  |  | 3,860 | 2,274
Distribution of shares of treasury stock for deferred directors’ compensation (in shares) | 2,707 | 6,426 | 2,707 | 6,426
Purchase of shares of treasury stock (in shares) | 5,831 | 117,880 | 28,706 | 122,021
Sale of shares of treasury stock (in shares) | 2,333 | 13,778 | 6,024 | 27,963
Forfeitures of shares of restricted stock awards (in shares) |  |  |  | 112

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