CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Issuance of common shares under stock based compensation awards	44,102	60,459
Common stock acquired for treasury	15,789	900
Common stock dividend (in dollars per share)	$ 0.46	$ 0.37