Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash dividends per share common stock (in dollars per share)	$ 0.11	$ 0.10
Shares of common stock purchased (in shares)	3,338	20,070
Shares of common stock issued (in shares)	557,530	2,104,305
Series C Preferred Stock
Cash dividends per share preferred stock (in dollars per share)		$ 2.50
Series D Preferred Stock
Cash dividends per share preferred stock (in dollars per share)	$ 17.50