Condensed Statements of Consolidated Changes in Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share) - Series A	$ 0.01		$ 0.01
Cumulative preferred stock shares authorized (in shares)	20,000,000	20,000,000	20,000,000	20,000,000
Common stock shares par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000	1,000,000,000
Common stock dividends declared per share	$ 0.2875	$ 0.2775	$ 0.5750	$ 0.5550
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share) - Series A	0.01	0.01	0.01	0.01	$ 0.01
Preferred stock dividends declared	30.6250	0.0000	30.6250	0.0000
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Cumulative preferred stock par value (in dollars per share) - Series A	0.01		0.01		$ 0.01
Preferred stock dividends declared	$ 17.5000	$ 0.0000	$ 35.0000	$ 0.0000