CONSOLIDATED STATEMENT OF CHANGES IN EQUITY AND OTHER COMPREHENSIVE INCOME (Unaudited) (Parenthetical) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018 USD ($) $ / shares	Jun. 30, 2018 USD ($) $ / shares
Statement of Stockholders' Equity [Abstract]
Cash dividends, per share (in dollars per share) | $ / shares	$ 0.39	$ 0.78
Common stock authorized, amount for future purchases | $	$ 590.1	$ 590.1