Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Consolidated Statements of Changes in Shareholders' Equity (Unaudited) [Abstract]
Cash dividend declared (in dollars per share)	$ 0.068125	$ 0.068125	$ 0.068125	$ 0.068125	$ 0.0656	$ 0.0656
Stock option exercises (in shares)	19,850		5,100	81,350	91,200	4,000
Purchase of treasury stock (in shares)			4,131	36,431	45,509
Sale of treasury stock (in shares)	74,656	76,443	86,297	65,928	70,792	65,289