Condensed Consolidated Statements of Changes in Equity (Unaudited) (Parentheticals) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Common Stock [Member]
Dividends per common share (in dollars per share)	$ 0.765	$ 0.72
Preferred Stock [Member] | Series H Preferred Stock [Member]
Dividends per depository share (in dollars per share)		1.2938
Preferred Stock [Member] | Series I Preferred Stock [Member]
Dividends per depository share (in dollars per share)	1.125	1.125
Preferred Stock [Member] | Series J Preferred Stock [Member]
Dividends per depository share (in dollars per share)	1.0313	1.0313
Preferred Stock [Member] | Series K Preferred Stock [Member]
Dividends per depository share (in dollars per share)	$ 1.0547	$ 1.0547
Additional Paid-in Capital [Member]
Sale of interests in investments, tax		$ 16