Common Stockholders' Equity (Schedule of Changes in Shares of Common Stock Outstanding) (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Common Stock Shares Outstanding [Roll Forward]
Balance, beginning of year	264,546,100	265,170,882	266,737,725
Shares issued	706,333	745,612	1,062,086
Shares repurchased	(8,707,676)	(1,370,394)	(2,628,929)
Balance, end of year	256,544,757	264,546,100	265,170,882