Total Equity and Other Comprehensive Income (Dividends per Share) (Details) - $ / shares		3 Months Ended		6 Months Ended
	Jul. 09, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Common Stock, par value $5.00
Class of Stock [Line Items]
Cash dividends declared, Common, per share (in dollars per share)		$ 0.95	$ 0.75	$ 1.90	$ 1.50
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)		0.45	0.45	0.90	0.90
Series O Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)				3,375	3,375
Series P Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)		1,532	1,532	3,063	3,063
Series Q Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)		1,344	1,344	2,688	2,688
Series R Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)		2,425	2,425	2,425	2,425
Series S Preferred Stock [Member]
Class of Stock [Line Items]
Cash dividends declared, Preferred, per share (in dollars per share)		$ 2,500	$ 2,500	$ 2,500	$ 2,500
Subsequent Event [Member]
Class of Stock [Line Items]
Cash dividends declared, Common, per share (in dollars per share)	$ 1.15