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Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Statement of Stockholders' Equity [Abstract] |  |  |
Stock Repurchased and Retired During Period, Shares | 3,578,743 | 43,560 | 24,271
Stock issued during period, new issues (in shares) | 19,491 | 4,356,973 | 3,848,929
Stock issued during period, RSU (in shares) | 332,085 | 212,587 | 214,892
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares | 34,912 | 46,198 | 43,079
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | 111,539 | 143,222 | 161,217
Shares tendered in payment of option price and income tax withholding amounts, shares | 26,124 | 47,971 | 38,450
Dividends declared (in usd per share) | $ 2.00 | $ 1.24 | $ 1.12

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