Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) (Parenthetical) - $ / shares	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Stock options exercised (in shares)		48,586
Cash dividend per common share (in dollars per share)	$ 0.56	$ 0.54

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

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