Condensed Consolidated Statements of Shareholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Purchase of shares of treasury stock (in shares)	26,932	75,980
Shares of common stock for the exercise of stock options (in shares)	68,284	260,481
Dividends declared per common share (in dollars per share)		$ 0.21

Number of share options (or share units) exercised during the current period.

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