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Equity And Earnings Per Share (Basic Table) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic earnings per share:
Net income available for common stockholders	$ 32	$ 32	$ 78	$ 81
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	77,357,609	75,868,349	77,054,388	75,486,825
Basic earnings per share	$ 0.41	$ 0.43	$ 1.01	$ 1.08
Common Class A [Member]
Weighted average shares of common stock outstanding:
Weighted Average Number of Shares Outstanding, Basic	77,357,509	75,868,249	77,054,288	75,486,725
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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