CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Stockholders' Equity [Abstract]
Issuance of common shares under stock based compensation awards	34,191	48,765
Common stock acquired for treasury	15,784	900
Common stock dividend (in dollars per share)	$ 0.22	$ 0.18