CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Statement of Stockholders' Equity [Abstract]
Issuance of common shares under stock based compensation awards	61,265	109,887
Common stock acquired for treasury	900	270,378
Common stock dividend (in dollars per share)	$ 0.56	$ 0.54