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Consolidated Statements of Equity (Parentheticals) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Retained Earnings [Member] |  |  |
Cash dividends, amount per share (in dollars per share) | $ 0.59 | $ 0.55 |
Cash dividends, amount per share (in dollars per share) | $ 0.59 | $ 0.55 |
Cash dividends, amount per share (in dollars per share) |  |  | $ 2.51
Special dividends, amount per share (in dollars per share) |  |  | 2.00
Cash dividends, amount per share (in dollars per share) |  |  | $ 2.51

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 + Details
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