Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Consolidated Statements of Changes in Shareholders' Equity (Unaudited) [Abstract]
Stock option exercises (in shares)	13,250
Cash dividend declared (in dollars per share)	$ 0.068125	$ 0.068125
Purchase of treasury stock (in shares)	6,305	489,000

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

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Balance Type:	na
Period Type:	duration