Condensed Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) - $ / shares		3 Months Ended
	Feb. 14, 2018	Mar. 31, 2018	Mar. 31, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per common share (in $ per share)	$ 0.45	$ 0.45	$ 0.45
Cash dividends declared per preferred share (in $ per share)		$ 1.8125	$ 1.8125