Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Stockholders' Equity [Abstract]
Dividends declared (in USD per share)	$ 0.2575	$ 0.255	$ 0.515	$ 0.51