Consolidated Statements of Equity (Unaudited) (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (in dollars per share)	$ 1.165	$ 1.06
Dividend equivalents declared per share (in dollars per share)	$ 1.165	$ 1.06