Condensed Consolidated Statements of Equity (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Dividends declared, per common share (in dollars per share)	$ 0.495	$ 0.480
Adoption of new accounting standard, tax	$ 2,869
Additional Paid-in Capital
Income tax on stock option exercise and other shares issued to employees and directors	$ 0	$ (323)
Stock option exercises and other shares issued to employees and directors, shares	134	122
Retained Earnings
Dividends declared, per common share (in dollars per share)	$ 0.495	$ 0.48