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Equity And Earnings Per Share (Basic Table) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Basic earnings per share:
Net income available for common stockholders	$ 46	$ 36	$ 124	$ 117
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	78,509,625	76,742,789	77,543,008	75,910,080
Basic earnings per share	$ 0.59	$ 0.46	$ 1.60	$ 1.54
Common Class A [Member]
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	78,509,525	76,742,689	77,542,908	75,909,980
Common Class B [Member]
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	100	100	100	100

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