Net Income Per Common Share (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Issuance of preferred stock	$ (1,000,000)	$ 394,000,000	$ 0
Depositary Shares, Issued	400,000	400,000
Preferred Stock, Dividend Rate, Percentage		5.625%
Preferred Stock, Liquidation Preference, Value	$ 100,000	$ 100,000
Preferred Stock, Liquidation Preference Per Share	$ 1,000	$ 1,000
Proceeds from Issuance of Preferred Stock, Preference Stock, and Warrants		$ 400,000,000