Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Cash dividends declared (in dollars per share)	$ 0.58	$ 0.57
Exercise of stock options (in shares)	8,769	2,650
Purchase of treasury shares (in shares)	75,110	181,899

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

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