Condensed Consolidated Statement Of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Issuance of common stock (in shares)	27,965	137,040	2,419	223,768
Cash dividend (in usd per share)	$ 0.65	$ 0.60	$ 0.60	$ 0.55

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

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